Thermo-mechanically squeezed graphene all-mechanical amplifier:

Sensitive amplification of mechanical motion is required in many fields of science. Here, we demonstrate widely tunable, broadband, and high gain all-mechanical motion amplifiers based on graphene/Silicon Nitride (SiNx) hybrids. In these devices, a tiny motion of a large-area SiNx membrane is transduced to a much larger motion in a graphene drum resonator coupled to it. Furthermore, the thermal noise of graphene is reduced (squeezed) through parametric tension modulation. The parameters of the amplifier are measured by photothermally actuating SiNx and interferometrically detecting graphene displacement. We obtain coupling gain of 38 dB and an overall sensitivity of 17 fm per square root Hz, close to the thermal noise limit of SiNx. Our results suggest that graphene resonators have potential as tunable, quantum-limited motion transducers and amplifiers at room temperature.

References

1. Giant Tunable Mechanical Nonlinearity in Graphene-Silicon Nitride Hybrid Resonator. Rajan Singh, Arnab Sarkar, Chitres Guria, Ryan J.T. Nicholl, Sagar Chakraborty, Kirill I. Bolotin, and Saikat Ghosh. arXiv:1904.01613 (2019). (pdf)

2. Motion Transduction with Thermo-mechanically Squeezed Graphene Resonator Modes. Rajan Singh, Ryan J.T. Nichol, Kirill I. Bolotin, and Saikat Ghosh. Nano Lett. 18 (11), 6719-6724 (2018). (pdf) (Supplementary Information)