Visiting professor brings experience to NQPI
November 30, 2010
By Benjamin White
NQPI’s faculty shows a little more diversity as Noboru Takeuchi, a celebrated physicist from the National Autonomous University of Mexico (UNAM), Ensenada, spends a year researching materials with the Department of Physics and Astronomy.
Takeuchi, who likes to be called Noboru around the department, had visited Ohio University several times in the past and chose to spend his sabbatical in Athens because he liked the town and respected the school’s dedication to nanoscience.
His work is mostly theoretical, what he calls “computational material science.” The research he conducts mostly deals with the properties of various materials used in experimental nanoscience. When NQPI scientists perform experiments, sometimes they cannot explain what they get.
“Sometimes, when studying surfaces, you do not know the atomic structure, you don’t know where the atoms are,” he explained. “I am just trying to explain the experiments, by making models.”
Takeuchi came to work with professors Sergio Ulloa and Nancy Sandler, but says he collaborates with faculty at NQPI. Recently, he partnered with NQPI director Art Smith in researching the growth of manganese on gallium nitride surfaces, key materials in emerging nanotechnology.
He earned a doctorate degree in physics from Iowa State University, and in his previous sabbatical year, Takeuchi worked at Princeton University, a school he loved because of its small size and idyllic campus not unlike OU’s.
Takeuchi brought his family to live with him in Athens while he conducts his research, and during their free time he says they love to walk around Athens and travel. When he completes his year of research at OU, Takeuchi will return to UNAM.
Throughout Takeuchi’s time at UNAM, Ensenada, which is close to San Diego, he headed the Department of Nanostructures and published around 100 articles in international journals , work that has been cited close to 1,500 times. He also wrote a popular and award-winning children’s book in Mexico.
UNAM, based in Mexico City, claims the largest number of students in the Americas. It also has four small foreign campuses in the United States and Canada that focus of Spanish and Mexican culture.
OU’s Glidden Visiting Professorship award, established in 1988, helped fund Takeuchi’s stay at the Department of Physics and Astronomy along with two other visiting professors.
Students showcase research at NQPI/CMSS Poster Session
November 11, 2010
By Benjamin White
The second and third floors of Clippinger Hall's atrium, normally silent on a Thursday afternoon, held a bustling crowd as Ohio University students exhibited their research at the annual NQPI/CMSS Poster Session.
Holding catered croissant sandwiches, students and faculty maneuvered around 51 posters as OU's brightest minds explained their work, some competing for money toward research. The posters presented the newest ideas in nanoscience and materials research.
The panel of faculty judges split the presenters in to undergraduate, graduate and post-doctoral categories. The top three posters from the graduate group would receive prizes totaling $475 to be used for research. Poster subjects ranged from the construction of a pulsed laser ultra-fine deposition system to bending a single protein.
First place for the post-doctoral category went to "Quantum Phase Transitions and Kondo Effect in Parallel Double Quantum Dots" by A. Wong, W. Brian Lane, L.G.G.V. Dias da Silva, K. Ingersent, N. P. Sandler and S. E. Ulloa. In the graduate category, "Phonon Mediated Relaxations and Exciton Lifetimes in Quantum Dot Molecule” by Kushal C. Wijesundara and Eric Stinaff prevailed, and "A Photoactive Platinum Sulfoxide" by Krystyna Chisholm and Jeffrey Rack won the undergraduate group.
Other posters that received medals include "Novel Structural Modeling Techniques for Amorphous Materials" by Bin Cai, Andrew L. Goodwin and David A. Drabold and "The Solvent Dependence of [Ru(bby)(biq)PYSO]2+" by Preston Roeper and Jeffrey Rack.
New NQPI professor explains research at public lecture
October 18, 2010
By Benjamin White
Dr. Alexander Govorov of Ohio University's Department of Physics and Astronomy gave a lecture on chiral nanostructures at Baker Center Wednesday as part of the College of Arts and Sciences' New Professor Lecture series. Dr. Govorov, a Russian native, recently earned his full professorship after almost a decade at OU, where he authored many of his 120 peer-reviewed articles.
Dr. Govorov, a member of NQPI, explained the basics of his theoretical work with chiral nanostructures, a new branch of nanotechnology that could have a profound and lasting impact on optical devices. Chirality, he explained, is the “handedness” of nanostructures when a nanostructure is non-superposable with its mirror image, not unlike left and right hands. A prominent example of a chiral object is the right-handed DNA strand.
The important biomolecules (proteins, DNA, sugars) are chiral by nature, and the stream of photons forming a beam of light can be manipulated into a chiral form as well. A microscopic beam of light can be chiral, he explained, if the electric field of the photons moves in a spiral pattern. When chiral light is passed through a solution containing chiral material, scientists can tell whether the structure of molecules in a solution (e.g. proteins) has a clockwise or counterclockwise nature to it by examining how the beam of light reacts with the solution containing chiral molecules.
This effect, however, can typically be seen with ultraviolet light. Seeing this effect with visible light would be easier and would open the door for new optical technologies.
Dr. Govorov proposed and modeled a system that does just that.
His proposal uses a gold nanocrystal, a giant (in molecular terms) cluster of gold atoms, and attaches it to a chiral protein. After putting the nanostructure into a solution, scientists would pass visible chiral light through the liquid. Govorov predicts the chiral light would change, making it easy for scientists to tell exactly which chiral proteins were in the solution. This effect has recently been confirmed experimentally by a group at Air Force Research Labs in Dayton and should have important ramifications on cutting-edge optical sensors and other nanotechnology.
Dr. Govorov obtained his Ph.D from the Institute of Semiconductor Physics at Akademgorodok in Russia and has been at Ohio University since 2001, when he moved to Athens as a visiting professor.
The New Professor Lecture Series has highlighted the research and creative work of each new professor in the College of Arts and Sciences for five years. Lectures are held on Wednesdays at 4 p.m., and video recordings of each lecture will be posted to Ohio University's Web site.
OU upgrades material growth system
September 25, 2010
By Benjamin White
An outmoded and virtually forgotten piece of machinery will receive a state-of-the-art facelift this year, thanks to NQPI's Dr. Savas Kaya.
OU's metalorganic chemical vapor deposition (MOCVD) system grew gallium nitride, an essential material for optoelectronics such as Blu-Ray lasers and delicate sensors for years, but recently it has lain dormant, taking up an entire room in Stocker Center. The 15-year-old machine was to be retired until Kaya and Dr. Wojciech Jadwisienczak, both of the School of Electrical Engineering and Computer Science, decided to apply for funding to fix the aging giant.
Ohio University awarded Kaya, in his ninth year at the school, $30,000 through the 1804 Fund, which will be used for the hardware updates. The other benefactors that includes the NQPI, CMSS Program and the College of Engineering will provide additional resources to support of a post-doctoral research scientist who will be in charge of testing and tweaking the MOCVD system to perfection and training his successor.
The upgraded MOCVD system will be able to produce zinc oxide as well as gallium nitride. ZnO, according to Dr. Kaya, is easier to grow and makes possible a wider variety of experiments, including those requiring finer nanostructures and work in spintronics. The machine's decrepit control center, originally a PC from the early 1990s, will be replaced by a high-end computer with an upgraded data acquisition interface and software.
“It'll make it more crispy and smooth,” explained Kaya, who compared the project with tuning up an old Pontiac GTO.
Dr. Kaya plans to buy the substrates required to grown zinc oxide and gallium nitrate instead of building them from scratch in order to devote more time to research. The annual cost of running the MOCVD system will fall between $10,000 and $20,000.
The semiconducting materials produced by the MOCVD system will be used in research along with the plasma-enhanced chemical vapor deposition (PECVD) system recently acquired by the School of Electrical Engineering and Computer Science's photonic sensors group. The combination of the semiconducting and insulating films grown in these complementary machines should “immensely benefit” OU in funding and recognition.
Hardware upgrades will be completed by spring 2011.
NQPI physicist looks to understand properties of supercooled glass
September 12, 2010
By Robin Donovan
Dr. Horacio Castillo, an Ohio University theoretical physicist, is currently completing work on the fourth year of a grant from the Department of Energy that has implications for our understanding of supercooled liquids, glasses, colloids and granular materials.
The initial grant was awarded for $254,987 in 2006. The project was later extended at no cost, then granted a one year $103,539 renewal in December 2009.
Castillo’s work seeks to characterize the glass transition that connects the liquid and the amorphous solid states. In a liquid, molecules move relatively quickly, but as temperature decreases, molecules move slower and liquids become more viscous. When a glass is formed, the molecules have essentially become frozen, caught in a disordered state, and the material is elastic, like a solid.
As the material transitions towards the glass state, Castillo said, “Not every part of this liquid is becoming slow in the same way, but actually if you manage to look at it microscopically, there are regions where the molecules are moving much slower than in other regions.”
Specifically, the funded study seeks to characterize how these inhomogeneous changes happen with numerical simulations and the creation of theories. Castillo’s research will further scientists’ understanding of viscosity, diffusivity and similar properties in supercooled liquids and glasses.
“We are doing a little bit of simulation and a little bit of theory and we are now starting to analyze experimental data, to see if this theory we’ve been developing is supported by the experiments,” said Castillo.
Castillo and his team at Ohio University have gathered experimental data from collaborators at Emory University, the University of Pennsylvania, and at Université Montpelier, France. They are also collaborating with groups at the University of Göttingen, Germany and at Bucknell University, who are working on simulations of granular materials. A renewal of the grant is in progress with the Department of Energy.
Scientists share STM techniques, expertise in Germany
August 24, 2010
By Robin Donovan
NQPI Director Dr. Art Smith recently returned from five weeks in Germany, where he provided scientific discussion and direction for an Ohio University-University of Hamburg collaboration in scanning tunneling microscopy (STM) that he said is “gaining momentum.”
The collaboration is in part the outgrowth of the National Science Foundation ’s Partnerships for International Research and Education (PIRE) grant, which has allowed NQPI members and others to collaborate with scientists from Hamburg, Germany to Buenos Aires, Argentina.
During his trip to Hamburg, Smith coordinated an informal site visit with a National Science Foundation representative, served as an on-site advisor to Ohio University student Andrew Dilullo in Hamburg and discussed ways to strengthen the collaboration with researchers at the University of Hamburg. One student from Hamburg is already in Athens, and four to five OU students hope to join the Hamburg research group next summer.
Because the techniques, tools and methods used in STM are so specialized, sharing knowledge and skills can help researchers leap forward in their work. For example, Dr. Saw-Wai Hla, who is an active NQPI member, shares his expertise about molecules on surfaces and the use of STM tips for atom manipulation with researchers in Hamburg. Smith plans to develop samples at OU for use on specialized machinery in Hamburg.
The research team in Hamburg provides world-renowned expertise in the use of spin polarized STM. “We have benefitted a lot just by having a student there. . . .We’ve learned a lot of technique and design concepts that are helpful to our research here,” Smith said.
The Ohio University-University of Hamburg collaboration will begin its fourth year in September. For additional information about this partnership, visit http://www.phy.ohiou.edu/spire/SPIRE/Welcome.html
.
Building a better binary: Harnessing phase changes speeds computing
August 18, 2010
By Robin Donovan
In the second year of research funded by the National Science Foundation, Dr. Gang Chen is developing technology that will harness phase changes to revamp computer memory systems. “We hope that we can improve this technology and make it faster and able to store more information,” he said, noting that phase change memory materials are already used in everyday devices such as Blu-Ray discs.
To build on this technology at the nanoscale, Chen synthesized hexagonally-structured nanoporous silica and germanium antimony telluride, or GST. When cooled and shrunken, liquid GST placed within this “honeycomb” solidifies faster and releases less heat.
“We could have a computer memory that’s at least 1000 times faster and store information at least 10 terabytes per square inch,’ he explained. So far, Chen and his research group have synthesized the nanoporous silica and GST and learned how to control the size and composition of each material.
“A year from now we hope that we can put these individual components together. Basically, we have to fill the honeycomb with honey,” he said. A myriad of parameters, including temperature, influence how a combined structure would self-assemble.
The project has implications for technology based on phase changes, or a material’s change from a disordered, amorphous phase to an ordered crystalline state. “Unlike random-access memory, this memory is nonvolatile, which means the information stored inside will be there forever,” Chen said. That means future students may carry an entire library on a memory chip and read books through handheld devices.
Ethical challenges not new, reminders helpful
August 14, 2010
By Robin Donovan
Saving money, saving lives and being environmentally friendly are oft-cited goals of research because they match societal values, but when ethical issues arise, scientists must consider the balance between progress and risk.
While nanoscience and nanotechnology pose few new ethical challenges compared to other emerging technology, these growing fields present an opportunity to incorporate the study of the ethical implications of science and technology into scientific curricula according to NQPI’s Dr. Arthur Zucker.
Zucker, a philosophy professor who has tackled applied ethics from business to medicine to nanotechnology, said, “Applied ethics is, in some sense, a lot of social and political philosophy. What are the roles of science and advances in technology in society?”
Advances in the beginnings nanotechnology and fields like medicine, computing, and communication are subject to value-related decisions. Questions such as, “What should scientists study?” and “What is a desirable outcome?” are at the core of applied ethics and social and political philosophy.
When ethics is integrated into existing courses, it becomes as much a part of the thought pattern of scientists as the scientific method. And that, Zucker wrote in an email, “just has to be a good thing.”
First NQPI engineer cuts production costs with nanoscale modeling
August 8, 2010
By Robin Donovan
Most engineers focus on the world at a macro level; graduate students in the field begin to work at a microscale. Dr. Gerardine Botte, whose research takes engineering to the nanoscale, brings a passion for practical applications and a desire to help engineers work more efficiently.
Botte joined NQPI this year after her involvement with the group as a grant proposal collaborator. In 2008, she joined Drs. Saw-Wai Hla, Ralph Whaley and David Ingram in writing a Department of Energy proposal that would harness an unusual collaboration between engineering and physics at the nanoscale.
The resulting $30 million project drew positive reviews, but was not funded due to budget restrictions. The true outcome, Botte noted, was setting up an infrastructure for future grants collaborations. “When NSF [the National Science Foundation] has an opening for one of the subtopics, because we had so many subtopics, I just say, ‘OK, Saw, David, we have a subtopic that matches. Do you want to go for it?’” The ease of this partnership is notable; physics and engineering are on opposite ends of Ohio University’s campus.
Ultimately, Botte and her collaborators planned to extract hydrogen needed for fuel cells from wastewater through electrolysis. For example, urine could be a cheap source of ammonia, itself an excellent hydrogen carrier.
Botte is currently focusing on modeling the deposition of platinum over surfaces using electrodeposition. By predicting the way this expensive element would be deposited on a surface, less of the material would be used in the trial-and-error stages of engineering.
“Platinum is a catalyst for many processes, so that would be a significant contribution to many different fields—batteries, fuel cells, even jewelry,” Botte said. Today’s engineers have parameters, but do not know the exact quantity of materials needed. By examining the process on a nanoscale, she hopes to lower the cost of using platinum as a catalyst during an upcoming sabbatical.
Hla heads to Japan with hopes of collaboration
July 31, 2010
By Robin Donovan
Despite their geographic separation, nanoscientists worldwide are currently shopping for tickets to Kobe, Japan, the site of NSS-6, a biannual nanoscience conference. More focused than larger conferences, NSS-6 takes an in-depth look at the latest advances in nanotechnology.
Professor Saw-Wai Hla, whose work recently appeared in Nature Nanotechnology, is a member of the conference’s international advisory committee. One goal of NSS-6 organizers was to “keep it small” he said, citing the conference’s intimate size as vital for discussion and collaboration. The five day event is expected to draw more than 100 people, many of whom are acquainted from previous conferences and collaborations.
NSS-6 presentations cover experimental areas of nanoscale research, including spectroscopy, synchrotron radiation, and laser-driven methods. Attendees will include scientists from various industries, academia and government-sponsored laboratories.
“It’s not big enough to be overwhelming and it’s not small enough so that we can’t include many important areas. It’s just big enough so that we can have good discussion and include many different people,” Hla said.
This year’s conference will be held in at Kobe University from October 25 to October 29. The conference location rotates between Europe, Asia and North America; NSS-5 was hosted by Ohio University in 2008.
The NSS-6 abbreviation represents the 6th International Workshop on Nanoscale Spectroscopy and Nanotechnology.
Mixing media: Journalism collaboration builds nanoscience awareness
July 16, 2010
By Robin Donovan
Journalism students collaborating with nanoscientists at Ohio University presented their internship program at a recent PIRE meeting in Arlington, Virginia. PIRE, or the Partnership for International Research and Education, is funded by the National Science Foundation. Ohio University students and scientists partner with collaborators in Argentina and Germany for nanoscale research and education.
The presentation helped audience members understand how scientists and journalists collaborate to bring awareness of nanoscience to the public. Alyse Zimmer, who traveled to Germany to cover research activity, and Emily Hubbell, who helped launch NQPI's newsletter, presented with Dr. Art Smith, NQPI's director and supervisor of journalism students working with NQPI and the SPIRE program.
For more information about the program, visit the SPIRE website
.
Quantum dot know-how leads to unusual internship
July 9, 2010
By Robin Donovan
While scores of doctoral students hunker down in laboratories this summer, Yueran Yan is moving to a new city, working for a new company, and making practical use of his lab skills.
After presenting his research at the American Chemical Society 's annual meeting in San Francisco last March, the president of Sun Innovations introduced himself to Yan. Following a brief email exchange, he offered Yan an internship at the company's laboratory in Fremont, California.
"I know a lot of people, they have the ability to do research, but they don't like to talk to people, they will be shy presenting in front of people. You need to tell people you can do it. I think that's the most important thing," Yan said.
Yan’s advisor, Dr. Greg Van Patten , encouraged him to present at the conference and said Yan will likely teach the company as much about quantum dots as he learns from them. “If nothing else, he’ll come back with a new understanding of how the materials he’s working with can fit into new technologies . . . . You see these scientific papers and you see that other people are working in this field, but these materials [quantum dots] haven’t really been used in the industry yet,” Van Patten said.
As an assistant engineer, Yan will synthesize quantum dots that function as semiconductors and can be tailored to customers' needs. Yan talked happily about this new challenge, describing himself as, "A little bit excited. I never worked at a company before. I've always just done research at a university in a lab. This is the first time I'm going to make a product that can be used in real life. I don't have a lot of experience with that, so I feel a little bit excited and nervous."
Yan's current work focuses on synthesizing quantum dots, or designer atoms, with two shells that protect unstable cadmium telluride at the dot's core. He explained, "We want to figure out the best material to use for biological applications like bio-imaging."
A research or development position in the bio-imaging or solar cell industry is Yan’s dream job. On a nanoscale, this might mean using dyes to identify different types or parts of cells. For example, bio-imaging could help surgeons identify cancerous tissue without guesswork. This could prevent the needless removal of healthy tissue and organs. In the solar cell industry, quantum dots can also be used as a source of white-light LEDs.
Yan is quick to admit that internships aren't a popular summer activity among his peers. "It's not common. Especially for the chemistry or physics department, we don't have an internship requirement," he said, noting the difference between these fields and disciplines such as engineering that tend to be more practical.
For chemistry students like Yan, long, uninterrupted lab hours make summer an ideal time for research. Some students may look for internship work toward the end of their doctoral degree program. Still, economic factors and the theoretical nature of some research can make academic work impractical in the business world.
Yan's internship at Sun Innovations will run through August 28th. In September, he will begin his fourth year as a doctoral student with Dr. Greg Van Patten's research group. He hopes to finish his degree in the next two years.
Fellowship win funds thin film research
June 30, 2010
By Robin Donovan
After months of anticipation, Mohammad Ebdah, a doctoral student in physics, won the annually-awarded Graduate College Fellowship on May 17. The award includes a $14,487 stipend and a tuition and fee waiver.
"I was so, so excited at that time because when I checked the results, I was at home and my wife was also waiting. When I checked, it was a very good surprise," he said. Graduate students from every department on campus were eligible for nomination.
As part of the application process, Ebdah and his advisor, Dr. Marty Kordesch, detailed Ebdah's proposed research for the next year. The Graduate Council reviewed a C.V., project summary, and three letters of recommendation from Drs. Kordesch, David Drabold and Saw-Wai Hla.
Kordesch, who has worked closely with Ebdah since becoming his advisor in 2007, described him as, “Fast, smart, motivated…He’s all the things you want,” and noted that Ebdah works as rapidly as he speaks.
The fellowship will allow Ebdah to research thin films that have implications for the future of energy technologies. His work deals specifically with a semiconductor thin films made from amorphous indium zinc oxide that is prepared using a reactive magnetron sputtering technique. Amorphous zinc oxide is typically is an insulating material, but the addition of indium yields some semiconductive properties.
To determine the electronic properties of the thin film, Ebdah will use ultraviolet photoelectron spectroscopy. With this technique, a photon beam hits the thin film, causing some valence electrons to be emitted. These photoelectrons are captured by a hemispherical detector and studied to reveal properties of thin films prepared with varying proportions of indium.
Other techniques Ebdah uses to determine optical and electrical properties of the thin film are spectroscopic ellipsometry and Hall Effect measurements, respectively. When light is reflected off the thin film, spectroscopic ellipsometry helps scientists measure the change in polarization of the light. This information reveals optical properties of thin films. The Hall Effect characterizes charged carriers by measuring a specific voltage change in relation to an electrical current and a magnetic field.
Ebdah's research has practical applications for nanoscale devices including thin-film transistors, solar energy panels, optical coating and anti-reflectors. Astronomers, for example, require telescopes that minimize reflectivity in order to maximize the intensity and resolution of images of faraway stars and galaxies.
After completing his master's degree in physics at Massachusetts' Clark University, Ebdah came to Athens in 2006 to begin work on a doctoral degree. Although his master's work focused on molecular magnetism, Ebdah's work with Kordesch deals with transparent conductive oxides, seeking to uncover the optical, electronic and electrical properties of thin films.
He expects to earn his degree at the completion of the fellowship, in the spring of 2011.
Ebdah cites the support of Kordesch as instrumental to his success. Along with helping Ebdah to publish papers, travel, attend conferences, and conduct research, Kordesch helped him to develop the habits of a scientist by giving Ebdah space to pursue his ideas. "When I come [to him] with some idea, he doesn't restrict me much. He has trust in his students." Ebdah noted that this helps foster self confidence, creativity and the ability to discuss and deliberate ideas in the academic community.
After graduation, Ebdah hopes to join the growing solar cell/solar energy industry, which he sees as the future of energy. "If you look at the last century, the whole world depended on oil. Right now, we can feel as scientists that it's the era of solar energy to replace the other energy sources," he said.
The Graduate College Fellowship is one of five full-tuition, stipend-bearing fellowships awarded annually to graduate students. Departments across campus that house graduate students can nominate one student for the awards.
Physicists observe new excited states of matter
June 14, 2010
By Robin Donovan
Entanglement has long intrigued physicists. Without physically touching, two entangled items react instantaneously and identically to stimuli applied to one member of the entangled pair. Scientists collaborating between Ohio University and the Eindhoven University of Technology in the Netherlands recently observed new excited states of matter through this phenomenon.
The study highlights the first observation of hybrid excitons and appeared as an Advance Online Publication in Nature Physics on May 23. The observance of hybrid excitons in particular brings physicists a step closer to quantum information processing.
Using lasers, scientists targeted electrons in quantum dots positioned near a metallic layer within a lattice-shaped atomic structure. When the laser struck the quantum dots, electrons leapt from low to high energy levels, creating quasiparticles called excitons.
Excitons consist of an excited electron and hole, or space left behind at the low energy of a semiconductor. As excited electrons relax, they release secondary photons that can be studied to reveal properties of quantum dots.
“Looking at the spectrum of emission, we understand more about the state of the electron. The spectrum gives us the information about the hybrid [entangled] state, the state of the exciton, and the state of the electron and how it’s entangled,” said Sasha Govorov , a theoretical physicist from Ohio University’s Nanoscale and Quantum Phenomena Institute who co-authored the paper.
Unlike previous research that examined this type of entanglement, this study used optics to more directly observe unusual electron states. As scientists examined the properties of photons given off by relaxing electrons, they were also able to identify hybrid excitons. These quasiparticles were created through entanglement of an electron from a quantum dot and electrons from the metallic film.
Quantum dots are groups of atoms five to 50 nanometers wide that function as “artificial atoms.” Controlled by voltage, they can be arranged to form designer crystal structures and have become a popular research topic.
In a 2003 study, Govorov and his co-authors predicted that hybrid exciton states would exist and be observable under certain conditions. Before this project, however, this type of electron entanglement had not been observed in the optical spectra.
Previous research demonstrated electron entanglement and a related Kondo effect on a microscale, but the effect could only be observed indirectly using measurements of electric current through a sample. The Kondo effect describes the electrical resistance of conduction electrons that become entangled with localized impurities. By conducting research with optics on a nanoscale, scientists observed electron interactions and entanglements with some properties of the Kondo state. They not yet able to observe Kondo excitons, but this milestone is the subject of active experimental research.
The Ohio University Biomimetic Nanoscale and Nanotechnology group
and Condensed Matter and Surface Science Program
provided funding for this research. Experimental work was led by Professor Paul M. Koenraad
and performed at the Eindhoven University of Technology. Koenraad’s team included Joost van Bree, Niek Kleemans, Andrei Silov, Joris Keizer, Rian Hamhuis and Richard Nötzel. Theory was developed by Govorov at Ohio University.
Mathematician joins NQPI
June 9, 2010
By Robin Donovan
Dr. Tatiana Savin, an assistant professor of mathematics at Ohio University, recently joined NQPI. Savin earned her Ph.D. at Lomonosov Moscow State University and is also a member of the Condensed Matter and Surface Science Program at OU.
For more information about Savin's research interests or recent publications, visit http://www.math.ohiou.edu/~tanya/
Creating cost-effective tools to study quantum dots
June 8, 2010
By Robin Donovan
Today’s technology industry is always looking for new ways to make smaller cell phones, sleeker laptops and ever-thinner television screens. Mauricio Garrido, a physics doctoral candidate, is helping researchers develop new tools to take tech to the quantum level.
Garrido works with quantum dots, tiny semiconductors that may provide a foundation for quantum computing in the future. “Quantum dots behave almost like an atom, so you can engineer the spaces between the energy levels. They’re designer atoms, if you like,” he said.
Garrido’s dissertation, “Quantum Optics and Coupled Quantum Dots,” includes his work with photoluminescence excitation and time-correlated experiments dealing with quantum entanglement.
Photoluminescence excitation is the process of creating excitons, which occur when a charged electron leaps from a low valence energy level to a higher conduction level, leaving behind a positively charged “hole.” An exciton is made up of the electron at a low energy level and the “hole,” which are bound together. When the charged electron returns to the valence level, it releases energy in the form of a photon.
When two electrons and two “holes” are bound together and recombine, the two resulting photons may be entangled. Entanglement, a phenomenon Einstein believed would invalidate quantum mechanics, is not yet physically understood. Garrido’s dissertation research will help other scientists study quantum dots that display this quirky trait.
Entangled photons are mathematically related even when physically separated. Despite the distance between them, they still depend on each other; if one is measured, the other “knows” this instantaneously. Garrido, with Professor Eric Stinaff , is developing a way to create this entanglement reliably. So far, they found a way to map energy levels in quantum dots and shift them using only light. This may allow future researchers to manipulate quantum dots without the costly, clunky machinery currently needed to manipulate electric fields during the super-short lifespan of excitons.
Originally from Bogotá, Garrido can appreciate what lowering the price of experimental physics might mean. Economic conditions in Colombia mean funding for physics research is limited, but lower-cost methods could help nations unable to fund expensive projects.
After graduating this spring, Garrido will venture into astrophysics. Originally drawn to physics by the hope of building a time machine as a kid, he defined a new goal after realizing that time travel would be difficult and impractical. “I’ve been focusing on technology for the sake of technology, but the most important aspect, which is life--my life, people’s lives--I’m totally neglecting,” he said.
His new position, a postdoctoral job at Columbia University in New York may not be the Colombia of his childhood, but promises a step toward understanding humanity a bit more. Garrido will join Dr. Daniel Savin
’s research group
, studying the ways that inorganic matter could become organic in an interstellar medium using merged ion beams.
Students take top honors in university-wide expo
June 4, 2010
By Robin Donovan
Twelve NQPI students and student groups took home top awards at Ohio University’s annual Student Research and Creative Activity Expo , which featured a range of projects from about 600 OU students representing disciplines from anthropology to social work to engineering.
Research was judged by OU faculty members before the expo opened to the public, but the real rewards came not from prizes, but the chance to share research results with the public said Di Xu, a graduate student in physics. Hundreds of students from local schools browsed research posters and presentations at the expo.
Journalism intern highlights collaboration in Germany
May 26, 2010
By Robin Donovan
While her peers sought much-needed sun and relaxation during spring break, Alyse Zimmer was hard at work. As an intern for Ohio University’s SPIRE program, she spent two weeks in Hamburg, Germany writing about nanoscientists at the University of Hamburg in March.
The SPIRE program is an international research and education collaboration among nanoscientists from Ohio University, the University of Hamburg and the University of Buenos Aires in Argentina. SPIRE represents a nanoscience version of the national Partnerships for International Research and Education (PIRE) program, which promotes international collaboration among scientists, engineers and students in these fields. The “S” in SPIRE stands for spin, an electron behavior studied by nanoscientists.
Zimmer interviewed students and researchers about their work and involvement with SPIRE, including Ohio University physics graduate student Kangkang Wang. Wang is a member NQPI Director Art Smith’s research group and worked with low temperature scanning tunneling microscopes in Germany.
Zimmer also attended the German Physical Society’s spring meeting in Regensburg, which included poster sessions and presentations. In between interviews and notes, she travelled to Munich, Berlin, and visited landmarks including the fairytale-like Neuschwanstein Castle near the Bavarian border.
Along with the mind-opening experience of working abroad, Zimmer found a personal connection to the scientists she interviewed. “The SPIRE Program and what they’re doing with STMs [scanning tunneling microscopes] is world-renowned. In Hamburg, all I kept hearing was they’re the best group of people doing what they’re doing in the world, so to be a part of that was amazing. I felt very honored and special to be able to talk to them,” she said, adding that she’d recommend the internship to students interested in study abroad and communications.
Zimmer completed her undergraduate coursework in March, and recently accepted a job offer from Pep (formerly Promotion Execution Partners), a marketing and brand promotion firm in Cincinnati. To read her work from Hamburg, visit http://www.phy.ohiou.edu/spire/SPIRE/News/News.html
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Physics students consider entrepreneurship
May 21, 2010
By Robin Donovan
A physics graduate degree might seem a blazed path to professorships, but adventurous students at Ohio University aren’t ruling out jobs in the business world. Students gathered on Wednesday for a presentation from Swati Ramanathan, a physics graduate student from NQPI who recently traveled to Italy to attend a conference at the intersection of physics, engineering and entrepreneurship.
Scientists with doctoral degrees often aspire to teach, but that path isn’t for everyone. The conference, hosted by the Abdus Salam International Centre for Theoretical Physics, gathered students from developing nations to discuss intellectual property, licensing, patents and career options outside academia. As part of the event, students created a science-based business plan.
Ramanathan’s group brainstormed a company that would manufacture and sell lights using a quantum dot film to replace typical phosphor coatings, yielding a more pure white light than conventional bulbs. Such a concept would make use of Ramanathan’s physics finesse and be market-worthy. Still, she advised students to stick mainly to science and hire a business-minded chief executive officer for budding enterprises.
The technology needs of developed versus developing nations were also debated. Ramanathan pointed out that in developed countries, technology can be pushed on a market driven by consumerism, while developing areas need to have market pull before a product can be marketed and sold. In other words, a product must fill a specific need in areas where consumers have less disposable income.
The conference, “Workshop on Entrepreneurship for Physicists and Engineers from Developing Countries,” was held in Trieste, Italy, from May 3 to May 7.
International postdoc finds a hint of home in Athens
May 12, 2010
By Robin Donovan
Luis Dias da Silva visited Athens for the first time during spring, when flowering trees and an explosion of greenery enliven the town. As an international fellow, he appreciated both the area and its residents. “It is a small town, but it has a lot of cultural activities going on. . . .I was very impressed with the international community here.”
His first connection to Ohio University and NQPI came from a conversation with Dr. Sergio Ulloa, an Ohio University physics professor and NQPI member. The men met in 2002 during Ulloa’s visit to the Federal University of São Carlos in Brazil, where Dr. Dias was a postdoctoral fellow.
Dias visited Athens for six months in 2003 to collaborate with Ulloa and Dr. Alexander Govorov, also an NQPI member. He headed back to Brazil, but returned to OU in 2004 as a postdoctoral fellow, working closely with Ulloa and Dr. Nancy Sandler of NQPI.
As he adapted to life in Athens, Dias found a hint of home while working with NQPI members. “Professors Ulloa and Sandler are both from Latin America, so our relationship was very close,” he said.
Dias left OU in 2007 after accepting a positions with the Oak Ridge National Laboratory and the University of Tennessee. These days, he is looking forward to returning to Brazil. He recently accepted an assistant professorship at the University of São Paulo, Brazil’s largest research university.
Dias studies theoretical condensed matter physics and works with computational studies of nanostructures, including computer simulations of electron-electron interaction effects. His recent publications include collaborations with NQPI members such as “Tunable pseudogap Kondo effect and quantum phase transitions in Aharonov-Bohm interferometers” (Physical Review Letters, 102 166806, 2009) and “Many-body electronic structure and Kondo properties of cobalt-porphyrin molecules” (Physical Review B 80 155443, 2009).
Annual retreat leads to collaboration, reflection
May 6, 2010
By Robin Donovan
Celebrating new members, grants and collaborations were top items on the agenda at the annual NQPI retreat this year. Members met April 16th and 17th to discuss accomplishments and goals of the institute and relax at the Carpenter Inn and Conference Center in Carpenter, Ohio.
NQPI is currently welcoming Drs. Eric Masson and Geraldine Botte, the newest of twenty-eight Ohio University faculty members to join the institute. Director Art Smith presented their backgrounds and the overall accomplishments of NQPI, which included twenty-one grants submitted during the past year with grant income of $1.2 million during the same period. Members noted that leveraging NQPI collaborations helped win grant funding.
Smith also discussed work on the long-awaited helium liquefier, which should be operational by late spring. The equipment is nearly ready, awaiting only electrical work and connecting lines.
Because NQPI members may be geographically separated on campus, located in separate floors, buildings, or even sides of campus, retreat organizer Dr. Sergio Ulloa organized research presentations to keep NQPI members informed about recent accomplishments across departments.
Botte, a professor of chemical and biomolecular engineering, explained the potential use of wastewater to produce the hydrogen needed for fuel cells. Ammonia can be extracted from wastewater and used to carry the hard-to-store hydrogen that powers fuel cells. Ammonia is readily available as a component of one very common wastewater: urine. Botte noted that college campuses may be an ideal site for harvesting ammonia.
Dr. Saw-Wai Hla followed Botte with an explanation of his recent, widely-discussed discovery of the world’s smallest superconductor through the use of scanning tunneling microscopy. The discovery of a superconductor at the nanoscale has implications for understanding superconductivity and possible nanotechnology based on superconducting nanowires. Hla is a member of the physics and astronomy department. His study was published in Nature Nanotechnology and featured on CBS news, among other media outlets.
An additional faculty presentation highlighted photochromism and molecular bistability, as Dr. Jeff Rack showed how shining light on certain molecules will cause them to briefly change color through photochromic isomerization. Drs. Horacio Castillo and Art Smith also discussed their research.
Most importantly, the retreat allowed members to ask questions and brainstorm new collaborations. Dr. Savas Kaya, assistant professor of electrical engineering, is currently on sabbatical at the University of California-Davis, but attended the retreat to discuss his work with the electrochemical annodization of aluminum and microsphere lithography.
Students were not forgotten at the retreat. NQPI members considered their roles as educators, discussing the importance of weekly NanoForums to prepare students for academic careers and to teach them to communicate with scientists outside their fields. Several attendees expressed interest in a team-taught core nanoscience course that would provide an overview for students in fields represented by NQPI.
Members also said a sad farewell to Mala Braslavsky, NQPI’s special events and outreach coordinator, who is leaving the institute after almost three years of dedicated service.
Scouts zoom in on nanoscience
April 30, 2010
By Robin Donovan
Fourth and fifth grade Webelos Scouts, the highest level of Cub Scouts, toured scanning tunneling microscope labs and learned what it means to be a physicist with Dr. Art Smith, NQPI’s director, on April 12th.
The scouts toured Smith’s scanning tunneling microscope (STM) labs and learned about the day-to-day life of a physicist while completing the requirements for a scientist pin. Physicists might travel the world or even cure cancer while studying the world at the nanoscale, Smith explained.
One nanometer is about a millionth of the size of a pinhead and “contains more exotic phenomena than you can imagine,” Smith said. The boys were intrigued by the size of the STMs used by researchers to view individual atoms, comparing the sound of the cryogenic vacuum pumping equipment to a washing machine.
The boys are members of a pack in Athens and are preparing for graduation into Boy Scouts.
Second grade students build clouds, knowledge
April 21, 2010
By Robin Donovan
Some students are taught to reach for the sky. Students at East Elementary in Athens learned to bring the sky into the classroom as they created clouds with Ido Braslavsky, associate professor of physics and astronomy recently.
Braslavsky taught an interactive lesson about clouds, molecules and gases to Mrs. Schultz’s second grade class as part of the outreach component of a program funded by the National Science Foundation.
With a Van de Graaff generator, a device that uses a moving belt to charge a metal sphere, he explained the basics of static electricity. Students giggled as a wig attached to the generator’s charged sphere stood on end, and were amazed to see sparks jump through the air to hit a grounded metallic sphere.
Second graders also learned to compare the weights of different molecules by adding the atomic mass of elements such as hydrogen, oxygen, nitrogen and carbon. “Some atoms really like each other – they stick together all the time,” Braslavsky said as he showed students how molecules form.
After the kids learned how atoms combine to form molecules like water and carbon dioxide, Braslavsky explained that carbon dioxide can take various forms, including dry ice. As students’ eyes widened, he poured water over dry ice to create a cloud in a cup for each child.
Although the second graders were disappointed that they were not allowed to drink the resulting mixture, they were content to watch Braslavsky take a careful sip. The result? “It tastes like soda pop without the fizz and without the sugar,” he said.
The students thanked Braslavsky with “put ups,” or praise, and an Elvis impersonation.
Hla team discovers superconductor
March 31, 2010
By Robin Donovan
An international team of researchers led by Dr. Saw-Wai Hla, associate professor of physics and astronomy, overcame Joule heating to display superconductivity in four pairs of molecules just .87 nanometers wide.
The study was released today in an advance online publication of Nature Nanotechnology . The team used scanning tunneling spectroscopy to document superconductivity in varying lengths of molecules of (BETS)2-GaCl4, an organic salt, on silver.
The study was funded by the U.S. Department of Energy. For more information visit Ohio University’s research reports
or access the article online
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Scientists study enzymes in plant cell wall
March 19, 2010
By Emily Hubbell
A plant’s cell wall is the reason a plant looks the way it does. It creates form and acts as the first line of defense against harmful bacteria and fungi. Although the cell wall is a fundamental component of a plant, key aspects of this extracellular structure are still undiscovered.
Scientists know the plant cell wall is a matrix produced by of thousands of enzymes, each one helping to construct the wall’s web-like structure by synthesizing various sugars and proteins to form glycoproteins. But in most cases, researchers still don’t know which enzyme adds which sugar during this web-building process.
Ohio University researchers are working to identify the enzyme responsible for adding the first sugar in one of the plant cell wall’s glycoproteins, the Arabinogalactan-Protein (AGP). The National Science Foundation awarded the team $261,206 for the study.
Scientists have already converted material from the plant cell wall into biofuel through microbial fermentation, but they lack the research needed to optimize the process, said Allan Showalter, the grant’s principle investigator, professor of plant biology and NQPI member.
“The primary goal is to better understand how the plant cell wall is put together,” Showalter said. “But if we can understand how to modify this particular enzyme, it may influence the ability to remove lignin from the cell wall to get to the cellulose you need for biofuel production.”
The OU researchers—Drs. Showalter, Marcia Kieliszewski and Ahmed Faik—have determined that the first sugar in the plant cell wall, a galactose residue, binds to the AGP at the location where the amino acid Hydroxyproline (HYP) appears within its sequence. They are now trying to determine which enzyme or enzymes attach the galactose to the HYP.
The team uses two techniques—proteomics and bioinformatics—to determine which enzyme(s) could cause this phenomenon. They have whittled down the list from thousands of enzymes to six strong candidates.
With proteomics, the researchers determine the amino acid sequences of numerous proteins contained in the cell membrane fractions associated with the transfer of galactose.
The next step is to identify corresponding genes and predict which genes will likely produce proteins that are targeted to the Arabidopsis plant’s Golgi apparatus with this enzyme activity.
One reason to use Arabidopsis is that all its genes have been sequenced, said Showalter. This means researchers know all the protein sequences, making the plant “essentially a library that can be searched.”
The other method, bioinformatics, lets the team compare plant wall enzymes to enzymes that perform similar roles in animals and other organisms. Specifically, they can search for protein domains associated with binding and transferring galactose residues.
Once they have selected candidate enzymes, the team tests each one in an assay. The researchers mix a HYP-containing AGP peptide with a radioactive version of galactose and then add the candidate enzyme to the reaction. After a two-hour incubation period, the scientists can determine whether the peptide is labeled with the galactose.
NQPI welcomes new members
March 17, 2010
By Robin Donovan
Dr. Eric Masson and Dr. Gerardine Botte have joined NQPI.
Dr. Masson, assistant professor of chemistry and biochemistry, specializes in bioorganic and supramolecular chemistry. He earned his Ph.D. at the Swiss Federal Institute of Technology in Lausanne, Switzerland.
Dr. Botte, associate professor of chemical and biomolecular engineering, researches in the areas of electrochemical engineering, power sources and fuel cells, numerical methods, mathematical modeling, material science, and electro-catalysis. She earned her PhD from the University of South Carolina.
Grad student receives Ovshinsky Student Award from APS
March 12, 2010
By Emily Hubbell
Graduate student Kendal Clark received the Ovshinsky Student Award from the American Physics Society's Division of Material Physics. This award supports young researchers so that they can participate in APS meetings sponsored by the material physics division. Clark is a member of the Hla and Kaya groups.
PNAS study shows antifreeze proteins can cause superheating of ice
March 8, 2010
By Emily Hubbell
Yeliz Celik, who recently earned her doctoral degree in physics, was first author on a study published in Proceedings of the National Academy of Sciences this month. Dr. Ido Braslavsky, Celik's advisor and an NQPI member at Ohio University, and Dr. Peter Davies of Queen’s University in Canada led the study.
The same antifreeze proteins (AFP) that keep organisms from freezing in cold environments also can prevent ice from melting at warmer temperatures, according to the research study.
Antifreeze proteins are found in insects, fish,bacteria and other organisms that need to survive in cold temperatures. These proteins protect the organisms by arresting the growth of ice crystals in their bodies. The new study not only has implications for understanding this process in nature, but also for understanding the superheating of crystals in technologies that use superconductor materials and nanoparticles.
Twenty years ago, researchers proposed thatantifreeze proteins can create superheating by suppressing melting attemperatures higher than the equilibrium melting point.
“During recrystallization, a larger ice crystal grows while a smaller one melts. Antifreeze proteins can help control both of these processes,” Braslavsky said.
The team’s study, supported by the National Science Foundation and the Canadian Institutes for Health Research, presents the first direct measurements of the superheating of ice crystals in antifreeze protein solutions, Celik said.
In addition, the researchers provide the first experimental evidence that superheated ice crystals can be stabilized above the melting point for hours, at a maximum temperature of about .5 degree Celsius. Superheated crystals rarely stay stable for long periods of time, and previous studies showed that stabilization only occurs under unique conditions, Braslavsky explained.
The researchers used two techniques in the study, fluorescence microscopy and sensitive temperature control of a solution within a thin cell. In order to track the position of the antifreeze protein on an ice crystal, the researchers attached a second protein to the antifreeze protein—the green fluorescent protein, which glows under certain conditions. The scientists then placed the antifreeze protein solution in the thin cell, which allowed them to observe the fluorescence signal from the protein while finely controlling the ice crystal’s temperature.
Although the study reveals that these proteins can suppress ice melting up to a certain point, the protein’s ability to suppress ice growth is much stronger. The hyperactive antifreeze proteins used in the study were more capable of suppressing melting than the moderately active ones, Braslavsky said.
These findings potentially could make the process of ice recrystallization inhibition more efficient for applications such as maintaining the quality of frozen foods, Braslavsky said.
“Antifreeze proteins that inhibit growth and melt are essential for protection against freeze and thaw damages,” he said. “Big crystals (that occur in the recrystalization process) separate cell walls and damage the integrity of the tissue.”
In additional to Celik, Braslavsky and Davies,co-authors of the study include Maya Bar of the Weizmann Institute of Scienceand Laurie Graham and Yee-Foong Mok of Queen’s University.
Team studies drug for potential pancreatic cancer treatment
March 2, 2010
By Emily Hubbell
The American Cancer Society estimates that of the 42,470 people diagnosed with pancreatic cancer last year, only about one in five will live more than one year after their disease was found. Scientists have yet to discover a cure for pancreatic cancer, and its standard treatment, gemcitibine, only extends a patient’s life expectancy by a few weeks.
With a $2.6 million grant from the National Institutes of Health, Interthyr Corporation and a group of Ohio University researchers are working together to develop a drug that could potentially treat pancreatic cancer.
“Receiving this grant is a significant step forward” said Dr. Doug Goetz, professor of chemical and biomolecular engineering and NQPI member. “The goal is develop a safe therapeutic for this devastating disease.”
Dr. Leonard Kohn—CEO of Interthyr Corporation and retired OU faculty member from the College of Osteopathic Medicine and the Edison Biotechnology Institute—will collaborate with an interdisciplinary group of OU faculty led by Doug Goetz. The team includes Drs. Kelly McCall, Steve Bergmeier, Mark McMills, Frank Schwartz, and Ramiro Malgor.
When bacteria enter the human body, particles shed from the bacteria bind to Toll-like receptors (TLR). These TLRs trigger an innate immune response that protects the body from harmful bacteria, Goetz said.
But what happens if this process occurs when it shouldn’t? That’s a question that led Kohn to apply a derivative of a compound currently used in thyroid disease treatment to pancreatic cancer treatment.
Pancreatic cancer cells and some other non-immune cells have been shown to have inappropriate TLR signaling. Instead of jump-starting the immune process, this signaling may result in inappropriate cell growth, the generation of inflammatory proteins and overall disease expression, he said.
The idea is to treat pancreatic cancer with compounds that would inhibit unwanted TLR signaling, he said. Work led by McCall has already shown that the compound, C10, decreases TLR signaling in cancer cells.
Over the next two years, the scientists will work to determine the exact mechanisms involved in the action of C10, identify derivatives of C10 that may show greater activity, and conduct studies to move toward clinical trials, he said.
Ultrafast spectrometer to facilitate femtosecond research
February 22, 2010
By Emily Hubbell
In the amount of time it takes for light to travel a mere one third of a micrometer, one femtosecond has already come and gone. A femtosecond—which clocks in at the length of one billionth of one millionth of a single second—is measured as 10 to the -15th power.
Although a femtosecond doesn’t last very long, there’s a lot going on at this timescale. Investigations at a femtosecond resolution can reveal key details behind phenomena that nano scientists have yet to fully understand,including the energy dissipation process, the photochemical event of vision and the change in an electron’s properties.
"You’re looking at timescales in which electrons relax inside nanostructures, where spins interact,"said Dr. Eric Stinaff, assistant professor of physics. "How do charges relax and get into their final state? That’s still an open question."
To help understand these processes, the National Science Foundation recently awarded four NQPI members $400,000 for a new ultrafast transient absorption spectrometer.
The five co-Principle Investigators on the grant are NQPI members Dr. Tadseuz Malinski, Dr.Jeffrey Rack, Dr. Stinaff and Dr. P Gregory Van Patten; and Dr.Jennifer Hines.
The spectrometer operates like a strobe light. After a molecule is hit with one laser, another pulse of light is sent through. The delay between the two beams is at a femtosecond resolution, allowing researchers to observe changes in the sample that happen during this ultrafast timeframe.
"There’s a lot of interesting chemistry and physics to be done at the femtosecond time scale," Dr. Stinaff said.
The device has a large range of excitation and detection wavelengths that make it adaptable to many different experiments. In the future, students will be trained to operate the spectrometer, Dr. Rack said.
Dr. Drut holds special seminar
February 11, 2010
By Emily Hubbell
Dr. Joaquin E. Drut, a postdoctoral researcher in the nuclear theory group at the Ohio State University, lead a special seminar yesterday for students and faculty. He presented a lecture titled, "What Can Lattice QCD do for Condensed Matter Physics?"
Physics grad student defends AFP thesis
January 12, 2010
By Emily Hubbell
Graduate student Yeliz Celik defended her doctoral thesis in November and will graduate with a doctoral degree in physics at the end of winter quarter. Her advisor is Dr. Braslavsky.
Celik’s thesis, “Experimental Investigation of the Interactions of Hyperactive Antifreeze Proteins with Ice Crystals,” reveals important findings about how antifreeze proteins (APFs) function.
AFPs are found in organisms that have to survive cold temperatures.The proteins protect these organisms by arresting the growth of ice crystals within their bodies.
The Braslavsky group was the first to use microfluidics in AFP research. With this technique, the researchers exchanged a solution around an ice crystal while maintaining fine temperature control, Celik said.
“We use these temperature-controlled microfluidic devices to study whether antifreeze proteins bind irreversibly or reversibly to ice surfaces,” she said.
The research revealed that antifreeze proteins bind irreversibly to the surface of an ice crystal. It also produced data demonstrating that AFPs can suppress ice melting.
Although the idea of superheating ice crystals in AFP solutions originated years ago, this was the first experiment to provide quantitative proof for the phenomenon.
Before joining the Braslavsky group in 2006, Celik earned her masters degree in science education from Bogazici University in Turkey. She plans to complete two years of post-doc research before teaching physics at the university level.
Celik says that having her work with AFPs published will be the most rewarding part of the research process.