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

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.