2026/07/23 by Dirui Wu, Ying Kit Tsui, Xavier Loh +8
#cond-mat.str-el #cond-mat.other
A considerable phonon thermal Hall effect was recently discovered across a diverse collection of materials. To clarify this enigmatic thermal Hall response in various insulators, we investigate the doped Mott insulator La5/3Sr1/3NiO4 as an example material system and reveal a characteristic phonon-dominated thermal Hall effect. As a sensitive probe of the transverse thermal response, the thermal Hall resistivity wxy exhibits an insulating-like temperature dependence wxy(T), a linear magnetic-field dependence wxy(H) near H=0, and a T-linear thermal Hall angle at low temperatures. The presence of similar phenomena across a series of insulators suggests that wxy serves as a unifying description of phonon thermal Hall effect, corroborated by an apparent correlation between the insulating-like wxy(T) and material's localized electronic state.