Dissipative vs dispersive coupling in quantum opto-mechanics: squeezing ability and stability

TL;DR

This paper compares dissipative and dispersive optomechanical couplings, analyzing their effects on squeezing and stability in cavity systems, revealing fundamental differences in backaction and squeezing capabilities especially in the bad cavity regime.

Contribution

It provides an analytical comparison of dissipative versus dispersive coupling effects on squeezing and stability, highlighting qualitative differences and stability diagram similarities.

Findings

Dissipative coupling reduces backaction and suppresses squeezing in the bad cavity regime.

Dispersive coupling maintains stronger squeezing capabilities.

Stability diagrams are similar for small detunings, differing mainly by sign change.

Abstract

Generation of squeezed light and optomechanical instability for dissipative type of opto- mechanical coupling is theoretically addressed for a cavity with the input mirror, serving as a mechanical oscillator, or an equivalent system. The problem is treated analytically for the case of resonance excitation or small detunings, mainly focusing on the bad cavity limit. A qualitative difference between the dissipative and purely dispersive coupling is reported. In particular, it is shown that, for the purely dissipative coupling in the bad cavity regime, the backaction is strongly reduced and the squeezing ability of the system is strongly suppressed, in contrast to the case of purely dispersive coupling. It is also shown that, for small detunings, stability diagrams for the cases of the purely dispersive and dissipative couplings are qualitatively identical to within the change of the sign of detuning. The results obtained are compared with those from the recent theoretical publications.