A distinct thermal Hall signal is observed in a quantum spin liquid candidate Ba3CuSb2O9. The transverse thermal conductivity shows a power-law temperature dependence below 50 K, where a spin gap opens. We suggest that because of the very low longitudinal thermal conductivity and the thermal Hall signals, a phonon Hall effect is induced by strong phonon scattering of orphan Cu2+ spins formed in the random domains of the Cu2+-Sb5+ dumbbells in Ba3CuSb2O9.
ASJC Scopus subject areas
- Physics and Astronomy(all)