Comment on Kuwahara et al., Intensity Interference in a Coherent Spin-Polarized Electron Beam, Phys. Rev. Lett. 126, 125501 (2021)

TL;DR

This paper critically examines Kuwahara et al.'s claim of observing electron antibunching, suggesting that the observed effects could be due to polarization-dependent emission rates rather than quantum interference.

Contribution

It provides an alternative explanation for the observed phenomena, challenging the interpretation of the original experiment as evidence of quantum interference effects.

Findings

The observed antibunching dip may be explained by polarization-dependent emission rates.

Strain-induced linear dichroism could account for the reported effects.

The paper questions the original interpretation of the experimental results.

Abstract

The claim that Kuwahara et al. [1] have reported the observation of a Hanbury Brown-Twiss electron antibunching dip (their Fig. 3) could possibly be explained as an electron source emission rate dependency on the light polarization. Strain on their GaAs/GaAsP sample is uniaxial, and one would expect a linear dichroism in the photoemission possibly as large as 15% [7] - much larger than the 0.1% reported effect. The same concern exist for circular polarized light.