Thermal Hall conductivity of polarized or layer-imbalanced states

Determine the intrinsic magnon thermal Hall conductivity of a field-polarized or layer-imbalanced state in Ag₃LiRh₂O₆, where contributions from oppositely ordered ferromagnetic layers do not cancel.

Background

The paper predicts that each ferromagnetic honeycomb layer of Ag₃LiRh₂O₆ has topologically nontrivial magnon bands with Chern number |C|=2 and a finite intrinsic magnon thermal Hall conductivity. Because the material is predicted to have A-type antiferromagnetic order, contributions from oppositely magnetized layers may cancel at zero field. A field-polarized or otherwise layer-imbalanced state could avoid this cancellation and exhibit a measurable thermal Hall response, but the authors leave this investigation unresolved.