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Published on: April 26, 2014
Doppler Gyroscopes: Frequency vs Phase Estimation
John C Howell1,2, Merav Kahn1, Einav Grynszpan1
1Racah Institute of Physics, The Hebrew University of Jerusalem, Jerusalem 91904, Israel.
Abstract:
We consider the fundamental roles of frequency versus phase in parameter estimation, specifically in the Sagnac effect. We describe a novel, ultrasensitive gyroscope based on the extremely steep frequency-dependent gain of a liquid crystal light valve. We provide compelling experimental evidence that the Doppler shift is fundamental in the Sagnac effect giving clarity to a long-debated question. We experimentally show orders of magnitude improvement in sensitivity relative to the standard quantum limit of a gyroscope based on phase estimation.
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