RQI Seminar | Germain Tobar, Detecting single gravitons with quantum-controlled mechanical resonators

QNC 1201

For those of you who cannot attend in person, you can also join remotely through Zoom with the following information: https://uwaterloo.zoom.us/j/95161764824?pwd=5cvVcQHGmYeZL5S3RzjFhdI0a7LYrx.1

Speaker

Germain Tobar

Title

Detecting single gravitons with quantum-controlled mechanical resonators

Abstract

The quantization of gravity is widely believed to result in gravitons - particles of discrete energy that form gravitational waves. But their detection has so far been considered impossible. Here we show that signatures of single gravitons can be observed in laboratory experiments. We show that stimulated and spontaneous single graviton processes can become relevant for massive quantum acoustic resonators and that stimulated absorption can be resolved through optomechanical read-out of single phonons of a multi-mode bar resonator. We analyse the feasibility of observing a signal from the inspiral, merger and post-merger phase of a compact binary inspiral. Our results show that single graviton signatures are within reach of experiments. In analogy to the discovery of the photoelectric effect for photons, such signatures can provide the first experimental evidence of the quantization of gravity.

[1] G. Tobar, S. K. Manikandan, T. Beitel, and I. Pikovski, Nature Communications, 15 7229 (2024).

[2] G. Tobar, Igor Pikovski, Michael E. Tobar, arXiv:2406.16898 (2024)

We encourage you to join us fifteen minutes early (at 2:00 pm) for coffee and snacks, generously funded by the Department of Applied Mathematics.