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arXiv · 1107.0542

Laser spot position dependent photothermal mode cooling of a micro-cantilever

Hao Fu·Cunding Liu·Yong Liu·Jiaru Chu·Gengyu Cao
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Abstract

We explore the laser spot position (LSP) dependent photothermal mode cooling of a micro-cantilever in a Fabry-Pérot (FP) cavity. Depending on the LSP along the lever, photothermal coupling to the first two mechanical modes can be either parallel or anti-parallel. This LSP dependent behavior is analyzed theoretically by a simple model, which is in quantitatively agreement with our experimental observation. From simulation, the parallel and anti-parallel coupling region is identified along the lever. We conclude that a more efficient mode cooling may be achieved in the parallel coupling region.

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Hao Fu, Cunding Liu, Yong Liu, Jiaru Chu, Gengyu Cao. 2011-07-04. Laser spot position dependent photothermal mode cooling of a micro-cantilever. https://doi.org/10.1364/ol.37.000584

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