LAUSR

Significance Modern quantum materials display numerous phases of electronic matter with many-particle quantum entanglement between the electrons. However, this entanglement is notoriously difficult to characterize experimentally. Recent experiments have shown that the thermal Hall effect (when in a magnetic field, there is heat flow in a direction transverse to a temperature gradient) is a sensitive probe of the many-electron quantum state. We propose that these observations detect the scattering of lattice vibrations (phonons) from electronic impurities and compute the influence of the electronic dynamics on the heat carried by the phonons. We also propose a specific mechanism for the thermal Hall effect in the “pseudogap” state of the cuprates, the entangled state that leads to high-temperature superconductivity at smaller electron density.