Absence of the polar Kerr effect in the helical loop-current model [Phys. Rev. Lett. 111, 047005 (2013)]

TL;DR

This paper clarifies that the helical loop-current model cannot produce a polar Kerr effect in cuprates, despite having a gyrotropic term and a non-zero Faraday effect, due to the symmetry of the reflection matrix.

Contribution

The authors correct their previous claim by showing that the helical loop-current model does not generate a polar Kerr effect because of the symmetric reflection matrix.

Findings

The model contains a bulk gyrotropic term.

The model produces a non-zero Faraday effect.

The reflection matrix remains symmetric, resulting in zero Kerr effect.

Abstract

We correct our claim made in Phys. Rev. Lett. 111, 047005 (2013) that the chiral texture of loop currents can explain the experimentally observed polar Kerr effect in cuprates. Although our model does contain a bulk gyrotropic term and produces a non-zero Faraday effect on transmission, the reflection matrix of light is, nevertheless, symmetric and gives zero polar Kerr effect.