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A high-reflectivity high-Q micromechanical Bragg-mirror

H. R. Boehm·S. Gigan·G. Langer·J. Hertzberg·F. Blaser·D. Baeuerle·K. Schwab·A. Zeilinger·M. Aspelmeyer
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Abstract

We report on the fabrication and characterization of a micromechanical oscillator consisting only of a free-standing dielectric Bragg mirror with high optical reflectivity and high mechanical quality. The fabrication technique is a hybrid approach involving laser ablation and dry etching. The mirror has a reflectivity of 99.6%, a mass of 400ng, and a mechanical quality factor Q of approximately 10^4. Using this micromirror in a Fabry Perot cavity, a finesse of 500 has been achieved. This is an important step towards designing tunable high-Q high-finesse cavities on chip.

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H. R. Boehm, S. Gigan, G. Langer, J. Hertzberg, F. Blaser, D. Baeuerle, K. Schwab, A. Zeilinger, M. Aspelmeyer. 2007-01-02. A high-reflectivity high-Q micromechanical Bragg-mirror. https://doi.org/10.1063/1.2393000

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