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arXiv · 0811.1780

Reduction and possible elimination of coating thermal noise using a rigidly controlled cavity with a QND technique

Kentaro Somiya
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Abstract

Thermal noise of a mirror is one of the most important issues in high precision measurements such as gravitational-wave detection or cold damping experiments. It has been pointed out that thermal noise of a mirror with multi-layer coatings can be reduced by mechanical separation of the layers. In this paper, we introduce a way to further reduce thermal noise by locking the mechanically separated mirrors. The reduction is limited by the standard quantum limit of control noise, but it can be overcome with a quantum-non-demolition technique, which finally raises a possibility of complete elimination of coating thermal noise.

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Kentaro Somiya. 2008-11-11. Reduction and possible elimination of coating thermal noise using a rigidly controlled cavity with a QND technique. https://doi.org/10.1103/physrevlett.102.230801

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