The Physics & Astronomy Colloquium Series presents Igor Pikovskii of Stockholm University, discussing "Detecting Single Gravitons with Quantum Sensing" on March 22.

Abstract: Quantum phenomena and gravity are usually relevant at vastly different scales. Nevertheless, the interface of gravity and quantum theory can become relevant even at low energies, with experimentally accessible signatures.

In this talk I will first give a brief overview of some results in this field from our group, discussing how post-Newtonian corrections can affect quantum interferometry with clocks. I will then focus on the possibility to detect single gravitons. We demonstrate how signatures of single-graviton-exchange can be observed in laboratory experiments. We show that for massive quantum acoustic resonators, absorption of single gravitons from background gravitational waves can be resolved through continuous quantum sensing of quantum jumps. Our results show that single graviton signatures are within reach of experiments. In analogy to the discovery of the photo-electric effect for photons, I will discuss how such signatures can provide the first (weak) experimental evidence of the quantization of gravity.