Severe violation of the Wiedemann-Franz law in quantum oscillations of NbP
arXiv:2205.12088 · doi:10.1103/PhysRevB.106.L041106
Abstract
The thermal conductivity (k) of the Weyl semimetal NbP was studied with the thermal gradient and magnetic field applied parallel to [0 0 1] direction. At low temperatures k(B) exhibits large quantum oscillations with frequencies matching two of several determined from the Shubnikov - de Haas effect measured on the same sample with analogous electrical current and magnetic field orientation. Both frequencies found in k(B) originate from the electron pocket enclosing a pair of Weyl nodes. The amplitude of the oscillatory component of the thermal conductivity turns out to be two orders of magnitude larger than the corresponding value calculated from the electrical conductivity using the Wiedemann - Franz law. Analysis of possible sources of this discrepancy indicates the chiral zero sound effect as a potential cause of its appearance.
26 pages, 9 figures
References in corpus (9)
- Weyl semimetal phase in non-centrosymmetric transition metal monophosphides
- Phonons become chiral in the pseudogap phase of cuprates
- Hear the Sound of Weyl Fermions
- Thermal resistivity and hydrodynamics of the degenerate electron fluid in antimony
- Thermopower and thermal conductivity in the Weyl semimetal NbP
- Role of axion electrodynamics in Weyl metal: Violation of Wiedemann-Franz law
- Thermal transport in compensated semimetals: a mystery explained
- Magnetotransport signatures of chiral magnetic anomaly in the half-Heusler phase ScPtBi
- Strong anisotropy of electron-phonon interaction in NbP probed by magnetoacoustic quantum oscillations