Highly sensitive temperature sensing via quadratic optomechanical coupling

TL;DR

This paper proposes a highly sensitive temperature sensor based on quadratic optomechanical coupling, leveraging the divergence of mechanical susceptibility near a critical point to achieve ultra-low temperature sensitivity enhancement.

Contribution

It introduces a novel temperature sensing method using quadratic optomechanical systems and the critical point phenomenon for ultra-low temperature detection.

Findings

Sensitivity increases by several orders of magnitude near the critical point.

Sensor maintains high sensitivity at low temperatures.

Driving strength near the critical point causes divergence in susceptibility.

Abstract

The effective frequency of a mechanical resonator can be tuned via the spring effect induced by quadratic optomechanical (QOM) coupling, and both spontaneous symmetry breaking and anti-parity-time phase transition were predicted in the QOM systems. Here, we show that the mechanical susceptibility can be enhanced significantly by driving the QOM system with a strong external optical field, and divergence will happen as the driving strength approaches the critical point (CP) for spontaneous symmetry breaking. Based on the CP, we propose a highly sensitive temperature sensor with a mechanical resonator quadratically coupled to an optical mode. We find that the sensitivity of the temperature sensor can be enhanced by several orders of magnitude as the driving strength approaches the CP, and the sensitivity of the temperature sensor remains high in the low-temperature limit. Our work provides an effective way to realize highly sensitive temperature sensing at ultra-low temperature in the QOM systems.