OHIO undergrad studies physics at German synchrotron facility
September 9, 2011
By Benjamin White
BESSY is big -- that's the overwhelming notion that strikes visitors to the giant laboratory in Berlin. Past security and through the postmodern lobby lies the control room, which looks eerily like the control panel of the Death Star. A few more doors and a spiral staircase lead to the floor of the Superdome-sized facility, where over 40 groups work fervently – time at BESSY is a rare and precious commodity. For Vincent Roberts, a senior studying physics at OU, it's just another day at work.
The Berlin Electron Storage Ring Society for Synchrotron Radiation (abbreviated in German to BESSY) opened in 1998 as a replacement for the original BESSY, which was founded in 1979. BESSY II, as the current incarnation is officially known, looks like a giant chocolate doughnut from above – its essence is a surprisingly thin tube which makes an enormous ring with a circumference of 240 meters. Through this tube travel hundreds of bunches of electrons fast enough to create light – many kinds of rare light – that scientists from across the world clamor to use in their research.
Roberts, barely 21 years old, is spending the summer studying at the Institute for Physics at Humboldt University in Berlin. He studies condensed matter under NQPI member Dr. Saw-Wai Hla at OU, and he does not take his good fortune for granted.
“I feel like many of the undergrads don't get a chance to go abroad very often,” he said. “It's a much better opportunity.”
BESSY is one of the most advanced labs of its kind in the world, and Dr. Antje Vollmer, a surprisingly young-looking woman, is a senior scientist responsible for helping dozens of visiting researchers use the equipment at any given time, even if they call in the wee hours of the morning. Vollmer describes her daily duties as 10-20% engineering, 10% research, 10% manual work and 50% kindergarten, and she seemed perfectly comfortable explaining the intricately complex machine to someone who had not cracked a science textbook since the Bush administration.
“We use electrons from an electron gun. It's actually not like a Star Wars type thing, but just a filament” she said.
From there, the electrons head to the microtron, a smaller version of BESSY's premier ring, to accelerate to 50 megavolts. Then, the electrons, usually in bunches, move to the main accelerator, the synchrotron where they get accelerated to 1.6 gigavolt and from there into the storage ring. In most circumstances, the ring contains 340 bunches of electrons in a space that could hold 400, creating a gap. In the gap travels one electron bunch, which researchers use as a timer. BESSY is the only facility of its kind in the world where scientists can obtain measurements with X-ray of variable polarization in femtoseconds (10-15), and researchers can also obtain special definition down to a picometer (10-12) Users can tinker with energy, polarization, temperature and many other variables to their liking.
“You can choose whatever you like at any time you like, without disturbing the system,” Vollmer said.
The electrons never leave the storage ring, but the light they emit at such high speeds travels to 46 “beam lines,” thin tubes that emerge from the giant ring to transport light to research stations. Aluminum foil covers virtually every surface of each beam line, making the scene look even more like science fiction. The foil helps evenly disperse heat when the beam line needs ‘baking’ to 150°C for a day or two to achieve ultrahigh vacuum.
Only one in three research teams vying for a week-long slot of “beam time” at BESSY will receive it. Though private corporations can buy research time (usually at the rate of 250 euros per hour, depending on the desired beam), BESSY is free to scholastic researchers working with grant money, and international referees determine which teams receive beam time.
“We do all sorts of unconventional things for a research facility like this,” said Vollmer, attaching her radiation badge.
Scientists from disciplines ranging from archeology and art to biology and medicine use BESSY’s beam lines to conduct their research. One of the more unusual projects involved the “Sky Disk of Nebra,” an ancient bronze disk which depicted the night sky and a boat with gold inlays. The 3,500 year-old artifact is believed to be the oldest depiction of the night sky. BESSY helped scientists blast the artifact with harmless synchrotron radiation-driven X-ray fluorescence, a tool that can determine the exact composition of materials without damaging or affecting them in any way. Scientists could then accurately match the materials to a geographic area of origin.
The results: the majority of the gold inlays were found to have originated from Austria. The boat, which already stood out aesthetically from the rest of the disk, was found to be crafted from gold from either Romania or Stonehenge. These findings shed light on trade and culture sharing in Bronze Age Europe, and also opened a multitude of questions for archeologists and historians.
BESSY’s bread and butter, though, is material science and data storage study. Much of the research currently conducted by the lab’s 75 in-house scientists surrounds solar cells. Vollmer and other scientists study the materials that convert light to energy by using X-ray spectroscopy to understand the most efficient way to move the charges in and out of the materials. This research could one day lead to “electronics with the personality of a silicon chip and the consistency of a plastic bag,” according to Vollmer.
BESSY II’s opening in 1998 cost roughly 100 million euro. It replaced the original BESSY, located in Wilmersdorf, which is now part of the SESAME synchrotron facility in Jordan. The original lab housed pioneering work on spin-polarized photoemission.
Though Roberts will probably not receive any experience on the beam lines, he will assist researchers and laboratory staff at BESSY while working at nearby Humboldt University. His group uses scanning tunneling microscopy to study materials which could lead to the next generation of solar cells and superconductors. Though he vaguely know he wants to enter the field of medical physics, Roberts has no idea where he will attend graduate school.
Dr. Vollmer took a personal interest in Roberts, making sure he makes the most out of the time spent at the giant playground for researchers. Though she admits the 24/7 pace is hectic and “everyone is stressed,” Vollmer enjoys her job.
“It’s fun – Tinker Toys for big kids.”
New helium liquefier system saves researchers time and money
September 8, 2011
By Benjamin White
After five years of planning, designing and building, NQPI finally has a renewable source of helium, one of the most important and expensive materials used in research like scanning tunneling microscopy (STM).
Ohio University's new helium liquefier facility, housed in Clippinger Research Annex, cost roughly $800,000 and will pay for itself in four to seven years, according to NQPI director Dr. Arthur Smith.
“For us, it's an economical issue as well as having a much easier, plentiful, efficient and reliable source of helium for our experiments,” he said.
Researchers use helium in heavy amounts to help cool their STM systems to the point where molecular motion slows, allowing for clearer readings. Dr. Saw-Wai Hla, an NQPI member and just one of several helium users, consumes as much as 200 liters of the precious element per week, which would cost up to $150,000 per year (if he could afford continuous operation). After scientists used the helium, it would vaporize and vanish into the atmosphere (poof!), never to be used again.
The new helium liquefier, which Smith believes is the first in Ohio, will recapture the helium gas and convert it back into its liquid state, ready to be reused.
The quantifiable advantages to the new system are simple: the university will no longer have to pay for mass amounts of liquid helium, and the gas will not be released into the environment. Other benefits will appear with time. Prior to NQPI's acquisition of the liquefier, scientists had to budget their helium usage into their grants, and sometimes labs could not perform research, waiting until a shipment of helium arrived.
Howard Dewald, interim dean of OU's College of Arts and Sciences with a background in chemistry, seemed proud of the new piece of machinery, which he helped plan and finance.
“It seemed like the right move to make,” he said. “Grants were key in being able to do the work.”
Besides the Graduate Education and Research Board (GERB) grant, which helps fund NQPI, OU's Department of Physics and Astronomy and an 1804 grant helped shoulder the costs. NQPI's grant for global collaborations - the Partnership for International Research and Education (PIRE) - also contributed $150,000.
Doug Shafer, an OU mechanical engineering graduate and current mechanical systems technician within the Department of Physics and Astronomy, was key in helping plan and construct the unique and complex system in a challenging environment.
“We have a problem with vibration, and we've [had to make] some time-consuming expensive modifications,” said Shafer, who originally lobbied to build an addition to Clippinger Laboratories to house the machine. Humidity and air control also posed hurdles in the construction of the liquefier, which takes up two separate rooms. The recently-renamed Clippinger Research Annex, which lies only yards away from the research areas at Clippinger Laboratories, used to be a zoology research center, but it now works quite well as the home for the new machine.
The helium liquefier system, which took between six and eight months to install after the rooms were obtained and fixed and electrical power was put into place, begins with piping from each lab (currently three) which use the helium. The pipes bring used helium gas, which is pumped into a giant inflatable sack. From there, the gas passes through a compressor and into 18 storage cylinders (at least twice as many will be purchased in the future), where they wait to enter the helium liquefier itself, which uses low temperature and high pressure to create the Joule-Thompson effect, turning the gas into liquid. Finally, the new helium liquid is piped into a giant storage tank and then transferred into wheeled delivery containers, ready for the next experiments. The helium liquefier, built by Linde, condenses 15-17 liquid liters of helium per hour.
“I think when you look at the workmanship of that facility, I would say it is second to none,” said Smith, who likened Shafer's engineering to ‘Swiss craftsmanship'. “We did a lot of the installation ourselves, via our shop guys. This was crucial for the success of the facility.”
Smith and Dewald expressed interest in eventually partnering with nearby hospitals, which also use helium for some equipment. The helium liquefier will be shown along with the Department of Physics and Astronomy's other facilities and labs at its Open House on November 5.
NQPI professor receives prestigious award for heart research
September 7, 2011
By Benjamin White
NQPI member and chair of OU's Department of Chemistry and Biochemistry Tadeusz Malinski was recently presented with the Doctor Honoris Causa award from Poznan University of Technology in Poland.
He received the highly esteemed award for his role in nanomedicine, nanotechnology and nanoengineering. During his acceptance speech entitled "Engineering the Heart", he presented his novel findings concerning the fundamental mechanisms which regulates the work of the beating heart. "…the discovery of this important mechanism was possible with the use of nanosensors implanted in the beating heart. This mechanism led us to design new solutions for heart preservation, transplantations and a new design of an artificial heart.
Along with the Doctor Honoris Causa distinction, which was presented entirely in Latin in a ceremony full of traditional robes, Malinski also received another award for "Benefiting Humanity" through his research.
“The award ceremony was a very special and unusual event,” he said. “It was attended by hundreds of people, including world-renowned professors.”
Malinski is known worldwide for his research and inventions related to the human heart vascular system, diabetes, aging and other contributions to the medical field. This award only adds to the slew of about 25 other notable honors Malinski has garnered throughout his career.
DiLullo works toward Ph.D., studies charge transfer in Berlin
August 17, 2011
By Benjamin White
Germany isn’t quite as weird for OU physics Ph.D. student Andrew DiLullo, at least not the third time around. As a fourth-year physics graduate student working with NQPI member Saw-Wai Hla, DiLullo has worked at the University of Hamburg for two semesters the past two years and is currently conducting research at Freie University in Berlin.
Dr. Hla, who will be dividing his time between OU and Argonne National Laboratory in Chicago next year, plans to continue advising DiLullo and his other students as they prepare their doctoral theses. DiLullo, the only Bobcat at the Department of Physics at Freie University, helps Drs. Katharina Franke and Nacho Pascual and their groups in experimental research.
Though the scanning tunneling microscopes (STM) at Freie University have similar capabilities as those in Athens, the molecules they will study are drastically different from the ones OU researchers obtain from chemists in France and Germany.
“All the labs have their own unique qualities,” DiLullo said. “Many of the molecules studied here are synthesized by chemists locally.”
Dr. Franke, with whom DiLullo spends most of his time, investigates the properties of single molecules and molecular networks that could be used in the next generation of electronic devices. Specifically, the group studies transport phenomena, the Kondo effect, molecular charge transfer, and the relatively new field of molecular switches. The majority of Franke’s work will be conducted at very low temperatures in vacuum to better observe fundamental physical properties of the molecules. The primary focus of DiLullo's research is charge transfer between different molecules in covalently bound chains.
The Department of Physics at Freie University currently collaborates with many German physics programs – including Humboldt University in East Berlin, where OU students Heath Kersell and Vincent Roberts currently study – to synthesize tiny molecular switches. Researchers change the state of these switches, which by definition have two positions, using light, electrons or a combination of the two. Once perfected, these switches will be invaluable for use in tomorrow’s electronics –computers that will run exponentially faster and hold many times more information in a chip the same size.
Since DiLullo, who plans to form his doctoral thesis around magnetic molecular systems, has studied in Germany twice before, he no longer sees Germany as such a foreign culture and has learned to appreciate fine German food and drink.
“When I was first here, I instantly recognized things that were new to me.” he said. “Now, with the novelty worn off, I feel very comfortable in a culture and environment which I had once thought of as strange.”
After the summer session concludes in late August, DiLullo plans to return to OU to continue his studies.
"Spin Triangle" shares ideas at workshop in Germany
July 23, 2011
By Benjamin White
After three days in Hamburg, Germany and 25 talks relating to nanoscience, the first official SPIRE workshop was declared a success.
The presentations, held all day from June 29th to July 1st at the Institute of Applied Physics at the University of Hamburg, dealt with subjects ranging from rotations in complex molecular machines to theoretical calculations for Galium Nitride surfaces to OU's new spin-polarized scanning tunneling microscope (SP-STM). Each talk lasted 20 minutes and preceded a ten-minute discussion.
Ohio University sent Drs. Sergio Ulloa, Nancy Sandler, Saw-Wai Hla, and NQPI director Arthur Smith along with visiting professor Noboru Takeuchi to present their research and exchange ideas. Graduate students Heath Kersell, Andrew Dillulo and Daniel Bergman made the trip to present their research as well. OU undergraduate physics major Vincent Roberts, who will be a senior this year, also attended to absorb as much as possible from the renowned researchers' discussions.
Bergman is currently spending the summer at the University of Hamburg performing research at the Institute of Applied Physics using one of the school's SP-STMs. Kersell and Roberts will spend the rest of the summer working at Humboldt University. Dillulo will spend the summer working at Freie University in Berlin.
Several speakers from the University of Buenos Aires in Argentina, the third school in SPIRE's “spin triangle” of collaboration, also gave talks from South America using Adobe Connect, a type of videoconferencing software.
“I think it's always a great excitement if both younger students and established professors from both sides can meet and exchange ideas at different levels,” said Dr. Roland Wiesendanger, head of the Scanning Probe Methods Group and co-organizer of the conference.
Both Arthur Smith, the other organizer, and Wiesendanger believe the workshop and continued cooperation between the University of Hamburg and OU benefit both programs immensely. Smith praised the Wiesendanger group's expertise in SP-STM (the University of Hamburg has nearly a dozen scanning tunneling microscopes), and Wiesendanger said the schools have “complementary expertise” in nanoscience and that he expects much in the future.
The workshop was not all work, though. After the presentations each day, members dined at a traditional German restaurant, viewed Hamburg from a church bell tower, and explored the city's canals (Hamburg has more canals than Venice) in a boat tour. After the workshop, participants were given a chance to witness a Ph.D. defense which dealt with spin-transfer torque manipulation on the nanoscale.
SPIRE, funded by a five-year, $2.5 million National Science Foundation grant, was founded in the fall of 2007 and focuses on nanoscience research, especially in the realms of magnetism and spintronics.
NQPI director and student flaunt new STM at workshop in Germany
July 23, 2011
By Benjamin White
At the SPIRE workshop in Hamburg, Germany on June 30, NQPI director Dr. Arthur Smith and recent Ohio University physics graduate Daniel Bergman were proud to present a talk on OU's new spin-polarized scanning tunneling microscope (SP-STM) and its new material growth systems.
Smith began the presentation with an overview of the SP-STM, which cost roughly half a million dollars and was designed by NQPI researchers. Bergman continued the talk by explaining the state-of-the-art material deposition systems contained in the unit.
The new SP-STM is capable of creating materials using two techniques: molecular beam epitaxy (MBE) and pulsed laser epitaxy (PLE). MBE, the only method OU researchers could use in the past, works by shooting the material in a gas form out of a tube like a can of spray paint. The newer system, PLE, works by firing a laser at targeted particles. The super-powerful laser forms a particle plume – forming gas straight from the solid state of the material – which is deposited on a substrate, forming a much more even and controllable surface than the MBE method. Up to five elements can be used for a single sample in rapid succession to form complex substrates that will help researchers experiment with new materials that could be used in future quantum computing.
The machine even has a wheel with ten spots where different materials can be placed. After the laser deposits one material, the wheel can quickly be turned and the process can be repeated, making multi-material creation easier and faster.
“Surprisingly, it's a lot harder to get together than you would think,” said Bergman.
At first, the SP-STM experimenters experienced noise problems – sound waves in the lab's ancient building (through both the air and the floor) created vibrations that interfered with the machines precise readings. To fix this, NQPI scientists and engineers mounted the entire microscope and material depositing system on pneumatic legs, making super-effective shocks which solved the sound vibrations from the building. To fix the acoustic vibrations (those traveling through the air), they rigged a box lined with vinyl, cotton and aluminum around the sensitive area. These materials blocked sound waves and preserved the sensitivity of the behemoth machine.
Currently, the researchers are experiencing problems with the PLE laser but engineers hope to get the machine up and running in the near future.
The new SP-STM opens many doors for NQPI researchers. New, more complex substrates can be made much more easily and quickly, and, since the machine performs at very low temperatures, researchers can now define single atoms, a feat which proved difficult with the old equipment which performed at room temperature.
“It's definitely given me a new look on performing research,” said Bergman.
Bergman is currently studying at the University of Hamburg, where the SPIRE workshop took place. The school, which is much bigger than Ohio University, has almost a dozen STMs, and Bergman's job is to help run research with one of them. He will be attending the University of Toledo as a graduate physics student in the fall.
“It's a sweet place to study abroad,” he said. “Everyone is here to help you.”
OU physics students study surface phenomena in Berlin
July 23, 2011
By Benjamin White
Two Ohio University physics students can say they are Berliners this summer. Third-year graduate student Heath Kersell and senior undergraduate physics major Vincent Roberts will help some of the best scientists in condensed matter physics conduct their research at Humboldt University on the east side of Germany's capitol.
Though both will work at the Institute of Physics at Humboldt, they will work in different areas because of their expertise and specializations. Kersell, a group member of NQPI’s Saw Wai-Hla, plans to work mostly in scanning tunneling microscopy (STM) to finish one of his Ph.D. projects dealing with surface phenomena. Roberts, who has yet to pick a specialization but plans to enter the field of medical physics, will also work with STMs while spending the majority of his time at BESSY II, a giant ring-shaped laboratory which produces rare, ultra bright photon beams from fast-moving electrons.
“I feel like many of the undergrads don’t get a chance to go abroad very often,” Roberts said. “It’s a much better opportunity to go out and visit other labs.”
The STM laboratories at Humboldt use varying temperatures – a big change from OU’s equipment, which operates at low temperatures. The extreme cold (4.2 to 75 Kelvin) helps to slow atoms down in order to better see them, but experiments at such low temperatures show little about applications in real-world situations. Humboldt’s researchers work more on application, which requires experiments conducted near room temperature. Both Kersell and Roberts also say the lab’s software is unique and its staff more laid-back.
“It’s more of a relaxed feel,” Roberts said. “It’s relaxed but the Germans are very efficient while they’re working. It’s kind of give and take.”
Kersell explained that one possible application of the work in his group is to improve solar cells. Currently, solar cells work by absorbing light, which excites electrons used to generate electricity. Unfortunately, the efficiency of solar cells rarely exceeds 30 percent.
“Scientists are trying to improve the efficiency,” he explained. “They’re making thin films, where you have one layer of some material that is able to absorb light in a certain way.”
Engineers can stack these layers upon each other to maximize efficiency and absorb most of the light spectrum. One type of thin film solar cell has been designed which absorbs ultraviolet light while remaining transparent. These solar cell films could be placed over or incorporated into windows.
“You could fill in all sorts of niche applications with these types of solar cell films,” Kersell said.
Roberts and Kersell join fellow Bobcat Andrew Dilullo, a fourth-year Ph.D. student, in Berlin this summer. Dilullo is working at the Free University on the west side of Berlin. All three participated in NQPI’s SPIRE workshop, which featured half-hour talks from researchers at OU, Hamburg University and the University of Buenos Aires in Argentina. The SPIRE workshop took place in nearby Hamburg from June 29th to July 1st. All three students are set to return to Athens at the start of fall quarter.
New research system for NQPI/SPIRE is “cool”
April 26, 2011
By Audrey Rabalais
After six long years of designing and constructing, NQPI and SPIRE students and faculty are finally seeing their 2005 sketches of a state-of-the-art research system jump from the paper into full-functioning reality. The new system includes a low-temperature, spin-polarized scanning-tunneling microscope for the investigation of surface spin and magnetic structures. The system also includes a laser to nucleate, or begin growth of, thin atomic layers as well as eight evaporators to stimulate continuous thin film growth inside the growth chamber – twice as many as the older system used by NQPI and SPIRE researchers.
The main difference between the new system and the older system is the STM, said Wenzhi Lin, a doctoral student who has been working on the system since 2005. The new STM will perform at very low temperatures. Atoms under the microscope become inert when they are cold. This takes the “jiggle” out of the atoms in the scanning tip of the microscope and the atoms of the sample, allowing for clearer pictures. The system will be cooled by liquid nitrogen and liquid helium.
The system was initially funded with a $427,000 grant from the Office of Naval Research. Additional funding came from National Science Foundation, the Department of Energy and Ohio University. The SPIRE/NQPI researchers lowered potential costs by designing the system themselves and constructing it in an on-campus machine shop. A system such as this designed and built commercially could cost as much as $2 million, said Arthur Smith, professor and NQPI director.
“Before the system is able to deliver the kind of unprecedented results it was designed for, a few small bugs still need to be worked out,” Smith said, “But this is normal.”
Lin said he hopes that the system will be completely finished within the next six months as he continues his work at NQPI as a postdoc.
“It is such a great opportunity to start from the very beginning of such an exciting project and I feel good watching the whole machine grow up,” Lin said.
Wang's research spins electronic data storage into the future
April 11, 2011
By Audrey Rabalais
The same semiconductor that lights up traffic signals is being harnessed by a researcher at Ohio University to store information in modern electronics.
Kangkang Wang, a PhD student and research assistant in OU's Nanoscale and Quantum Phenomena Institute (NQPI), presented his research on two-dimensional manganese structures on the gallium nitride growth surface to members of NQPI on Friday, February 11.
Wang has spent the last year and a half manipulating the two elements to create a thin magnetic film that rests on a semiconductor. With these, he creates the possibility of using the spin of the electrons involved to store data in electronic devices. Older technology becomes a problem when electronics shrink in size due to increased power consumption per unit volume which causes overheating and wasted energy. By using electrons rather than magnets or other materials, these electronic devices become smaller, smarter versions of their ancestors. This field of study is known as spintronics.
“Spintronics is said to be offering advantages of higher processing speed, reduced power consumption, nonvolatility and increased density of storage,” said Wang. “Spintronics is not really a brand new idea. It has already been implemented in several electronic applications such as hard drives.”
Wang chose gallium nitride and manganese because their combinative properties make controlling and moving the electrons easy. Gallium nitride is a semiconductor and manganese is a ferromagnet when coupled with gallium. Manganese can be grown in a crystalline structure on top of GaN, without combining with it, allowing scientists to finely manipulate the spin of the electrons. The two elements form alloys with stable magnetic properties, which means the spin structure of the atoms is also stable.
“If we can prepare some of these atoms with very well-defined spin structure, we can manipulate the spin as we wish. Then we can possibly make use of the spin to store some information,” Wang said.
By using a scanning tunneling microscope (STM), Wang and other researchers can visualize the layout of the atoms so in the future they can move and manipulate them at will. However, for this project, Wang did not have technology that could keep up with his lofty research plans. He spent much of his time updating old equipment and building a completely new, spin-polarized STM.
“We are doing frontier research in science, so we often have to build our machines,” said Saw-Wai Hla, Associate Professor of Physics. “If you are at the highest point of a skyscraper, you still want to go up higher, so you have to set up your own ladder to climb up.”
Wang said the project was completely finished in November 2010. In October 2010, he won the Leo M. Falicov Student Award for his work at the AVS 57th International Symposium & Exhibition. The prestigious award is given to one student every year and includes $1000 cash. Wang's research has been accepted for publication in the Physical Review B Journal of the American Physical Society.
NQPI newcomer generates interest with Cucurbiturils
March 29, 2011
by Benjamin White
Eric Masson may be a new face at NQPI, but he hopes to make a large impact on a molecular scale as he and his group delve into the fascinating field of supramolecular chemistry.
Masson, an assistant professor in the Department of Chemistry and Biochemistry at Ohio University since 2007, earned his Ph. D. in organic chemistry from the Swiss Federal Institute of Technology, Lausanne in 2005, and spent two years at Yale University as a post-doctoral fellow in bioorganic chemistry. He joined NQPI last year for its collaborative opportunities and research capabilities.
Masson's group works in the overlapping realms of physical organic, bioorganic and medicinal chemistry, and is focused on host-guest recognition chemistry between various synthetic assemblies, as well as DNA and proteins.
Masson has recently attracted attention for his molecular machines that incorporate Cucurbiturils, pumpkin-like hollow macrocycles that are currently generating a tremendous interest in the supramolecular community. Those unique systems display extreme affinity towards a variety of guests, and can undergo mechanical motion along organic axles, once triggered by an external stimulus, such as pH changes, heat or light. The Masson group has recently investigated the kinetic and thermodynamic self-sorting properties of such systems, and has published the first case of an organometallic reaction catalyzed by Cucurbiturils.
Masson says that “in addition to their theoretical and aesthetic appeal, those nanometer-scale assemblies can be applied to areas as diverse as catalysis, data storage, chemical sensing, and the controlled release of anti-cancer, anti-malaria, wound healing or anti-macular degeneration drugs.”
Masson lives with his wife in Lancaster, Ohio, and besides supramolecular chemistry, he enjoys backpacking around the World, photography, and playing the piano.
Mathematician joins NQPI to model nanostructures
March 16, 2011
By Benjamin White
Physics and math have always fascinated Dr. Tatiana Savin, and her position as newest member and sole mathematician at NQPI will allow her to work at their intersection.
Savin came to Ohio University five years ago and, after learning about a possibility of collaboration with scientists studying material science, joined NQPI in May. Analysis is her specialty within the realm of mathematics, which complements material science nicely.
“When I learned NQPI exists, of course I wanted to join them,” Savin said.
Savin knew she wanted to study math and physics in high school when she interned at the Metal Physics Institute of the Russian Academy of Science in the Department of Theoretical Physics. In college, she held a summer job at Russian Academy of Science’s Institute of Solid State Physics studying amorphous alloys.
Savin worked on her master's thesis participating in biomedical research involving Nitinol, an alloy with shape memory, by making stents for use in angioplasty to correct arterial stenosis. Previously the standard procedure for angioplasty was to insert a compressed, spiral shaped stent into a narrowed portion of the artery and release it. The expanding spiral widens the artery to increase its blood flow. The use of the stent made out of the shape memory alloy makes the procedure significantly more efficient, since the spiral then can be straightened into a small piece of a wire at the room temperature which makes it easy to insert into an artery. Savin’s contributed to this project by determining the precise composition as well as the heat and deformation treatment of the stent to ensure the desired phase transition occurs at the human body temperature.
After receiving her master's degree, Savin worked on the design of bimetallic rods for a transport nuclear reactor regulating system. She also served in a national program to prevent nuclear disasters like Chernobyl by conducting numerical simulations of failures in the nuclear power reactors following an accidental loss of the coolant.
“I always enjoyed more doing a theoretical part of any research rather than experimental. That is why I received Ph.D. in mathematics from Moscow University,” Savin said.
Before she arrived in Athens, Savin worked at Technion (Israel) and Northwestern University as a mathematician in a team of physicists and engineers in the field of nanotechnology. She worked in the areas of crystal growth, thin films, quantum dots and nanowires.
Savin’s mathematical research interests are in the fields of complex analysis and differential equations. Her current interest to free boundary problems can help real life problems related to materials science and fluid dynamics. Her works in progress involve the Hele-Shaw problem and theoretical justification of vapor-liquid-solid model (VLS) for growth of nanowires. VLS growth, where a layer of liquid in which a soluble crystal material is situated between the vapor and growing crystal, was discovered by Wagner and Ellis half a century ago. The whiskers grown then had diameters on the micron scale, but smaller wires with a diameter of about 50 nanometers were grown recently. Savin hopes to one day create a shape of the liquid/solid interface in a VLS model.
Former NQPI member leading research in China
February 16, 2011
By Benjamin White
Former NQPI professor Liwei Chen has taken his expertise in nanoscience 10,000 miles to his home in China, where he heads the International Laboratory (i-LAB) and is currently the vice director of the Suzhou Institute of Nano-tech and Nano-bionics (SINANO), part of the larger Chinese Academy of Sciences.
Liwei, who earned his Ph.D. in Chemistry and Chemical Biology at Harvard in 2001 after obtaining master’s and bachelor’s degrees from Peking University and the University of Science and Technology in China, respectively, worked as an assistant professor in Ohio University’s Department of Chemistry and Biochemistry and was a member of NQPI from 2004 to 2008.
Now, he runs an important research institute in Jiangsu, one of the most economically vibrant provinces in China. He oversees the research activity of SINANO, which employs more than 700 personnel, through strategic planning and active grant administration. SINANO entered phase II construction in 2010 and will actively recruit research talents to expand its engineering and translational research in the next three years.
Liwei credits NQPI as an example of administrating interdisciplinary research with great success and has modeled some aspects of SINANO after NQPI. Furthermore, Liwei said NQPI made his time at Ohio University much more enjoyable.
“I have made friends with professors across multiple disciplines and various departments,” he said. “Overall, [NQPI] added a lot to my experience at OU.”
Liwei’s research group is currently focusing on interfacial nanomaterials and their applications in solar energy harvesting, lithium ion batteries, nanocomposite fibers and nano-bio interfaces. Their research has led to the development of quantitative electric force and dielectric force microscopies used to study individual single-walled carbon nanotubes. The research team has recently achieved one of the highest efficiency organic/inorganic hybrid solar cells in the world.
The Suzhou Institute of Nano-tech and Nano-bionics also hosted the fifth Sino-US Nano Forum, which was held on June 5-7, 2010.
Dr. Arthur Smith reelected as NQPI director
February 7, 2011
By Benjamin White
After tallying the votes, it became official: Ohio University physics professor Arthur Smith will serve his third consecutive three-year term as NQPI's director.
Smith, who has been a member of NQPI since its inception in 2001, says he took some convincing to give the demanding position a third go-around.
“It has been a tremendous amount of work,” admits Smith, who joined Ohio University's Department of Physics and Astronomy in July 1998. He also heads the school's NSF SPIRE international collaborative campaign, which connects OU with the University of Hamburg in Germany and the University of Buenos Aires in Argentina to study nanospintronics and nanomagnetism. As well as the two directorships, Smith is also a member of OU's Condensed Matter and Surface Science Program and teaches graduate and undergraduate classes.
Few would have foreseen the success NQPI would become when it was launched in 2001 as part of the university's nanoscience initiative within its Doctoral Enhancement plan. With Smith as its second director, beginning in 2005, NQPI won $169,000 annually in base funding in OU's GERB competition, and established an international presence three years later when OU hosted the biannual International Workshop on Nanoscale Spectroscopy and Nanotechnology. Several of its members have been awarded lucrative and prestigious grants for their research.
In the future, Smith hopes to continue to build the name of NQPI, attract more funding and obtain a new building on campus dedicated to nanoscience. His goals also include increased mentoring of younger faculty and to establish a “nanocore” curriculum, a series of graduate classes which will be team-taught by NQPI faculty.
Smith, who obtained his Ph.D. at the University of Texas at Austin, has experienced much success in nanoscience, from receiving the U.S. Presidential Early CAREER Award in Science and Engineering in 2000 to obtaining an image of a Gallium Nitride spiral that was featured on the cover of Science in 1998. All in all, Smith has received about $5 million in external grants for research and collaborations.
An election was held for the position, but Smith was the only NQPI member to run.
Prof gives public lecture on quantum physics
February 7, 2011
By Benjamin White
A packed house of Ohio University students and Athens residents listened intently in the normally-bustling Front Room coffee house at Ohio University's Baker Center as NQPI physics professor Eric Stinaff lectured on the future of quantum computing.
The future of computers, he said, will use an “entirely new paradigm... something that fundamentally depends on the laws of quantum mechanics to perform its computation.”
Humanity's current technology, including cell phones, computers and video games, could have been easily explained to traditional physicists like Isaac Newton, Dr. Stinaff explained, because all electronics function in accordance with the traditional laws of physics and understandable phenomena like magnetism. New models of quantum computing operate on such a small scale that they must fundamentally utilize quantum physics, a murky and relatively recently-discovered world of strange physical laws within every molecule.
Dr. Stinaff explained that historically, it has taken roughly a century to utilize new discoveries in science for the engineering of new products. For instance, electricity and magnetism were first studied and written about in the 1700s, but the first electrical engineering department in England did not appear until 1885. The laws of quantum mechanics, while not always fully understood, have been studied for roughly 100 years, and the first quantum engineering program has already been started in Japan.
Quantum mechanics may sound strange and abstract to the average person, but these physical laws apply to every atom of material in the universe. Dr. Stinaff focused on two quantum properties of matter, superposition and entanglement, that could be used to create a faster, smaller computer.
Superposition concerns a property of subatomic particles called spin. Spin is angular momentum, more easily described as a magnetic force that can only be found in two states, like a penny lying face-up or face-down. The tricky part, scientists have found, is that before spin is measured as up or down, the particle seems as if it exists in both states at once, like a penny balanced on its side. The state of a particle that is both spin-up and spin-down is called superposition.
Computer engineers could use particles in superposition by using the electron's spin as the bit in binary code. Current computers simply recognize whether an electron is in a slot to determine whether there is a “1” or “0” in the binary code. Since particles in superposition can be both spin-up and spin-down at once, each particle, in theory, would be able to show two states: “1” and “0” at the same time or interchangeably. This would make computers exponentially smaller and more efficient.
Another quantum property that could be used in information processing is entanglement, such a strange phenomenon that Einstein called it “spooky action at a distance.” When Dr. Stinaff asked his colleagues observing the lecture if they understood entanglement, he only drew laughs.
“Quantum mechanics is kind of like a bad trip,” Dr. Stinaff explained. “It's kind of weird.”
When scientists entangle two particles, a process too complex for Dr. Stinaff to explain, they form a unique bond. When the spin of one particle is measured as spin-up, the other will always be measured as spin-down, no matter where they are in relation to each other. If two particles are entangled in New York City and one is flown to Los Angeles, as soon as the one in Los Angeles is measured, the one in New York City will measure the opposite.
While no scientist claims to understand the phenomenon of entanglement, this discovery could be of some use for computer engineers and cryptologists. Quantum entanglement is already being used for ultra-secure communication by the military and at least one private company.
Though some supercomputers currently rely on quantum mechanics, a complete overhaul of computers remains doubtful. More likely is a shift of certain components of computers like video cards or hard drives to incorporate quantum technology, Dr. Stinaff said.
Science Cafés at the Front Room Coffee House showcase Ohio University scientists' work and offer a venue for interested students and members of the community to converse with the brightest minds at OU. All lectures start at 5 p.m. Every other Wednesday. For more information visit www.ohio.edu/sigmaxi/sciencecafe .
NSF grant lets professor study bright future of LEDs
January 18, 2011
By Benjamin White
The National Science Foundation recently awarded NQPI member Wojciech Jadwisienczak of the Russ College of Electrical Engineering and Computer Science a Career Grant of $444,000 over five years to study new materials for use in future optoelectronics, photonics and spintronics.
Dr. Jadwisienczak, known as “Dr. J” around campus, teaches undergraduate and graduate courses and studies semiconductor materials, their devices and related technologies. The central focus of his research is the incorporation of rare-earth ions in III-Nitride semiconductors and their alloys. These ions (typically RE (3+)) have several interesting and profitable traits like producing a very pure color when excited by different means, including electrical current. The III-Nitrides technology has already hit the market in the form of Blu-ray players, which use a very small pure blue laser to read information packed into smaller chunks than DVDs.
One of Dr. Jadwisienczak's goals is to study materials which contain different rare earth ions and have interesting optical and magnetic properties. For example, Erbium, one of the most intriguing members of the lanthanide family, emits light at the wavelengths used by fiber optic cables, so it could prove to be very valuable in the telecommunications field due to an expected reduction in signal attenuation. Dr. Jadwisienczak explained that scientists have been trying to harness and use the strange properties of the rare-earth ions that occur naturally.
“We are simply lucky to have this opportunity, a case of an Erbium ion electron energy level fitting exactly to the telecommunication window,” explained Dr. Jadwisienczak. “Recent successes in developing Erbium-doped silicon-based compounds give hope that one day this opportunity will become a reality.”
Rare-earth ions could possibly also be used to overcome the current limitations of the III-Nitride technology in producing red light emitting diodes (LEDs). For quite a long time, scientists have been attempting to fabricate an InGaN alloy having the high indium content necessary to generate red light needed for a full technological integration of all primary colors. It was not possible until recently, when a group of researchers in Japan engineered a way to efficiently use Europium, another rare-earth element, to produce very pure red LEDs.
When scientists find a way to create the three primary colors efficiently, they could make ultra-small LEDs which could improve technology, creating a new generation of high-definition flat TV screens and displays.
Currently, blue, green and red lasers use different semiconductors, but Dr. Jadwisienczak envisions a “one-pot” model in which materials emitting the three primary colors could be created using the same growth system. He also aims to increase the energy efficiency of the light emitters based on rare earth-doped III-Nitrides operating in ultraviolet and near the infrared spectral range.
Dr. Jadwisienczak has collaborated with NQPI partners on projects related to materials growth, characterizations and device development for more than a decade. Especially, he says, his alliances with NQPI professors Arthur Smith, Marty Kordesch and Savas Kaya, to mention only a few, are important for the success of his CAREER project thanks to existing collaborative efforts and shared visions in research.
The National Science Foundation's Career Grants are highly selective and only available to non-tenured researchers.
Please see OU Office of Research's article: Engineering Profs Receive NSF CAREER Grants for Nanotechnology Research .