Strengthening weak value amplification with recycled photons

TL;DR

This paper proposes a recycling scheme for photons in weak-value amplification experiments to enhance measurement sensitivity by effectively increasing photon power without sacrificing amplification.

Contribution

It introduces a novel photon recycling method in weak measurements, improving sensitivity while addressing beam degradation effects.

Findings

Recycling photons increases effective power in weak measurements.

The scheme maintains amplification while enhancing sensitivity.

Beam degradation can be mitigated through profile flipping or Zeno reshaping.

Abstract

We consider the use of cyclic weak measurements to improve the sensitivity of weak-value amplification precision measurement schemes. Previous weak-value experiments have used only a small fraction of events, while discarding the rest through the process of "post-selection". We extend this idea by considering recycling of events which are typically unused in a weak measurement. Here we treat a sequence of polarized laser pulses effectively trapped inside an interferometer using a Pockels cell and polarization optics. In principle, all photons can be post-selected, which will improve the measurement sensitivity. We first provide a qualitative argument for the expected improvements from recycling photons, followed by the exact result for the recycling of collimated beam pulses, and numerical calculations for diverging beams. We show that beam degradation effects can be mitigated via profile flipping or Zeno reshaping. The main advantage of such a recycling scheme is an effective power increase, while maintaining an amplified deflection.