Hall Effect in Nested Antiferromagnets Near the Quantum Critical Point

TL;DR

This paper studies how the Hall coefficient changes in nested antiferromagnets near a quantum critical point, revealing an abrupt increase linked to Fermi surface changes and consistent with experimental data.

Contribution

It provides a theoretical explanation for the abrupt change in the Hall coefficient at magnetic ordering in nested antiferromagnets, connecting it to Fermi surface topology and impurity effects.

Findings

Hall coefficient increases abruptly at magnetic transition

Scaling of Hall coefficient with residual resistivity and impurity concentration

Consistent explanation for experimental observations in doped chromium

Abstract

We investigate the behavior of the Hall coefficient in the case of antiferromagnetism driven by Fermi surface nesting, and find that the Hall coefficient should abruptly increase with the onset of magnetism, as recently observed in vanadium doped chromium. This effect is due to the sudden removal of flat portions of the Fermi surface upon magnetic ordering. Within this picture, the Hall coefficient should scale as the square of the residual resistivity divided by the impurity concentration, which is consistent with available data.