Precision frequency measurements with interferometric weak values

Precision frequency measurements with interferometric weak values

We demonstrate an experiment which utilizes a Sagnac interferometer to measure a change in optical frequency of 129 ± 7 kHz/√Hz with only 2 mW of continuous-wave, single-mode input power. We describe the measurement of a weak value and show how even higher-frequency sensitivities may be obtained over a bandwidth of several nanometers. This technique has many possible applications, such as preci...

Weak-values Amplification: When Precision Measurements Become Easy

Reconstructing weak values without weak measurements

I propose a scheme for reconstructing the weak value of an observable without the need for weak measurements. The post-selection in weak measurements is replaced by an initial projector measurement. The observable can be measured using any form of interaction, including projective measurements. The reconstruction is effected by measuring the change in the expectation value of the observable due...

Weak-values technique for velocity measurements.

In a recent Letter, Brunner and Simon proposed an interferometric scheme using imaginary weak values with a frequency-domain analysis to outperform standard interferometry in longitudinal phase shifts [Phys. Rev. Lett105, 010405 (2010)]. Here we demonstrate an interferometric scheme combined with a time-domain analysis to measure longitudinal velocities. The technique employs the near-destructi...

Corrections for Wavelength Variations in Precision Interferometric Displacement Measurements

Precision interferometric displacement measurements require deadpath corrections to account for variations in wavelength during the course of the measurement. This paper discusses common errors in applying deadpath corrections and describes the correction necessary to fully account for variations in wavelength.