Strong phonon-cavity coupling and parametric interaction in a single microcantilever under ambient conditions

Abstract

Parametrically tuning the oscillation dynamics of coupled micro/nano-mechanical resonators through a mechanical pump scheme has recently attracted great attention in areas ranging from fundamental physics to various applications. However, the special design of the coupled resonators and the requirement for low-dissipation operating conditions significantly restrict the wide application of this tuning technique. In this study, we show that under ambient conditions, a mechanical pump can parametrically control the oscillation dynamics in a single commercial microcantilever resonator. Strong phonon-cavity coupling with a cooperativity of up to ∼398 and normal-mode splitting is observed in the microcantilever. The parametric interaction with the phonon-cavity coupling enables a mechanical pump to achieve 43 dB for parametric amplification and 3 dB for parametric cooling, respectively. Utilizing a mechanical pump, the potential sensitivity and signal-to-noise ratio of frequency-modulated Kelvin probe force microscopy operated in the ambient environment can be significantly improved by ∼16 times and 31 dB, respectively. Furthermore, both single-mode and two-mode thermomechanical noise-squeezing states can be created in the microcantilever by the application of a mechanical pump.