Complementary weak-value amplification with concatenated postselections

TL;DR

This paper demonstrates enhanced weak-value amplification in a Sagnac interferometer by using two concatenated postselections, leading to improved measurement sensitivity of transverse momentum kicks.

Contribution

It introduces a novel approach of combining two postselections in weak-value amplification to achieve greater signal amplification in interferometric measurements.

Findings

Improved signal amplification with concatenated postselections.

Polarization-dependent phase mismatch enhances weak-value amplification.

Darkport monitoring reveals complementary amplification effects.

Abstract

We measure a transverse momentum kick in a Sagnac interferometer using weak-value amplification with two postselections. The first postselection is controlled by a polarization dependent phase mismatch between both paths of a Sagnac interferometer and the second postselection is controlled by a polarizer at the exit port. By monitoring the darkport of the interferometer, we study the complementary amplification of the concatenated postselections, where the polarization extinction ratio is greater than the contrast of the spatial interference. In this case, we find an improvement in the amplification of the signal of interest by introducing a second postselection to the system.