Enhanced Laser Cooling of a Mechanical Resonator via Zero-Photon Detection

TL;DR

This paper demonstrates a novel method for cooling a mechanical resonator below its laser-cooled state by using zero-photon detection, opening new possibilities in quantum control and thermodynamics.

Contribution

It introduces and experimentally verifies a zero-photon detection technique for cooling mechanical resonators, advancing quantum measurement and control methods.

Findings

Successful cooling below laser-cooled occupation via zero-photon detection

Verification of cooling through heterodyne measurements

Theoretical modeling with stochastic master equation

Abstract

Throughout quantum science and technology, measurement is used as a powerful resource for nonlinear operations and quantum state engineering. In particular, single-photon detection is commonly employed for quantum-information applications and tests of fundamental physics. By contrast, and perhaps counter-intuitively, measurement of the absence of photons also provides useful information, and offers significant potential for a wide range of new experimental directions. Here, we propose and experimentally demonstrate cooling of a mechanical resonator below its laser-cooled mechanical occupation via zero-photon detection on the anti-Stokes scattered optical field and verify this cooling through heterodyne measurements. Our measurements are well captured by a stochastic master equation and the techniques introduced here open new avenues for cooling, quantum thermodynamics, quantum state engineering, and quantum measurement and control.