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A Precision Angle Sensor using an Optical Lever inside a Sagnac Interferometer

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 Added by Jason Hogan
 Publication date 2011
  fields Physics
and research's language is English




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We built an ultra low noise angle sensor by combining a folded optical lever and a Sagnac interferometer. The instrument has a measured noise floor of 1.3 prad / Hz^(1/2) at 2.4 kHz. We achieve this record angle sensitivity using a proof-of-concept apparatus with a conservative N=11 bounces in the optical lever. This technique could be extended to reach sub-picoradian / Hz^(1/2) sensitivities with an optimized design.



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