Anomalous Amplification of a Homodyne signal via Almost-Balanced Weak Values

Abstract

The technique of almost-balanced weak values amplification (ABWV) was recently proposed [Phys. Rev. Lett. 116: 100803 (2016)]. We demonstrate this technique using a modified Sagnac interferometer, where the counter-propagating beams are spatially separated. The separation between the two beams provides additional amplification, with respect to using colinear beams in a Sagnac interferometer. As a demonstration of the technique, we perform measurements of the angular velocity in one of the mirrors of the interferometer. Within the same setup, the weak-value amplification technique is also performed for comparison. Much higher amplification factors can be obtained using the almost-balanced weak values technique, with the best one achieved in our experiments being as high as $1.2\times 10^7$. In addition, the amplification factor monotonically increases with decreasing post-selection phase for the ABWV case in our experiments, which is not the case for weak-value amplification at small post-selection phases.

4 pages, 3 figures. comments are welcome

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Cited by in corpus (7)

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• Investigating the Effects of the Interaction Intensity in a Weak Measurement
• Practical Advantages of Almost-Balanced-Weak-Values Metrological Techniques
• Progress and Perspectives on Weak-value Amplification
• Quality analysis for precision metrology based on joint weak measurements without discarding readout data