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

Parametrically tuning the oscillation dynamics of coupled micro/nano-mechanical resonators through a mechanical pump scheme has recently attracted great attentions from fundamental physics to various applications. However, the special design of the coupled resonators and low dissipation operation conditions significantly restrict the wide application of this tuning technique. In this study, we will show that, under ambient conditions, mechanical pump can parametrically control the oscillation dynamics in a single commercial microcantilever resonator. A strong phonon-cavity coupling with cooperativity up to ~398 and normal-mode splitting are observed in the microcantilever. The strong parametric interaction of the phonon-cavity coupling enables using mechanical pump to achieve a 43 dB (3 dB) parametric amplification (cooling). By utilizing mechanical pump, the force sensitivity and signal-to-noise ratio of the frequency-modulation Kelvin Probe Force Microscopy can be significantly improved in the ambient environment. Furthermore, both single-mode and two-mode thermomechanical noise squeezing states can be created in the microcantilever via applying mechanical pump.