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arXiv · 1003.3752

Measuring nanomechanical motion with an imprecision far below the standard quantum limit

G. Anetsberger·E. Gavartin·O. Arcizet·Q. P. Unterreithmeier·E. M. Weig·M. L. Gorodetsky·J. P. Kotthaus·T. J. Kippenberg
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Abstract

We demonstrate a transducer of nanomechanical motion based on cavity enhanced optical near-fields capable of achieving a shot-noise limited imprecision more than 10 dB below the standard quantum limit (SQL). Residual background due to fundamental thermodynamical frequency fluctuations allows a total imprecision 3 dB below the SQL at room temperature (corresponding to 600 am/Hz^(1/2) in absolute units) and is known to reduce to negligible values for moderate cryogenic temperatures. The transducer operates deeply in the quantum backaction dominated regime, prerequisite for exploring quantum backaction, measurement-induced squeezing and accessing sub-SQL sensitivity using backaction evading techniques.

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G. Anetsberger, E. Gavartin, O. Arcizet, Q. P. Unterreithmeier, E. M. Weig, M. L. Gorodetsky, J. P. Kotthaus, T. J. Kippenberg. 2010-03-19. Measuring nanomechanical motion with an imprecision far below the standard quantum limit. https://doi.org/10.1103/physreva.82.061804

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