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arXiv · 1604.00189

Laser cooling of high temperature oscillator by multi-level system

Hoi-Kwan Lau·Martin B. Plenio
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Abstract

We study the laser cooling of a mechanical oscillator through the coupling with a dissipative three-level system. Under a background temperature beyond the Lamb-Dicke regime, we extend the standard cooling analysis by separately studying the classical motion and the quantum dynamics of the oscillator. In Ladder-system cooling, the cooling rate degrades by orders of magnitude at large classical motion. This phenomenon causes a critical transition of the final temperature at a hot background. In stark contrast, electromagnetic-induced-transparency (EIT) cooling with a $Λ$-system produces significant negative cooling rate at high motional excitation. At steady state, the oscillator could exhibit both cooling and lasing behaviours. We argue that a successful EIT cooling requires either a poor quality oscillator to suppress the lasing effect, or terminating the cooling process at a transient stage.

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Hoi-Kwan Lau, Martin B. Plenio. 2016-04-01. Laser cooling of high temperature oscillator by multi-level system. https://doi.org/10.1103/physrevb.94.054305

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