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Résumé |
The combination of low mass density, high frequency, and high quality-factor make graphene mechanical resonators very attractive for applications such as force sensing, mass sensing, and exploring the quantum regime of mechanical motion. Microwave optomechanics with superconducting cavities offers exquisite position sensitivity and
enables the preparation and detection of mechanical systems in the quantum ground state. Here, I will present our recent work [1] in which we demonstrate optomechanical coupling between a multilayer graphene resonator and a high-Q superconducting cavity. We achieve a displacement sensitivity of $27 fm/\sqrt{Hz}$ and measure mechanical quality factors up to 220,000. Optomechanical coupling is demonstrated by optomechanically induced reflection (OMIR) and absorption (OMIA) of microwave photons. We observe 17 dB of mechanical microwave amplification and the onset
of normal mode splitting, both signatures of strong optomechanical backaction. We extract the cooperativity C, a characterization of coupling strength, quantitatively from the measurement with no free parameters and find C=8, promising for the quantum regime of graphene motion.
[1] V. Singh, S. J. Bosman, B. H. Schneider, Y. M. Blanter, A. Castellanos-Gomez, G. A. Steele. Optomechanical coupling between a graphene mechanical resonator and a superconducting microwave cavity.
http://arxiv.org/abs/1403.5165 |
