Impurity-Induced Anomalous Thermal Hall Effect in Chiral Superconductors

Area of Science:

• Condensed Matter Physics
• Superconductivity
• Topological Materials

Background:

• Chiral superconductors possess unique properties influenced by their order parameter topology, Fermi surface, and excitation spectra.
• Impurities significantly impact electronic heat transport in these materials, leading to observable phenomena.

Purpose of the Study:

• To investigate the origin and characteristics of anomalous thermal Hall conductivity in chiral superconductors induced by impurities.
• To establish a quantitative relationship between the anomalous thermal Hall conductivity and the properties of chiral superconductors and impurities.

Main Methods:

• Theoretical analysis of electronic heat transport in chiral superconductors.
• Modeling of impurity scattering and its effect on Bogoliubov quasiparticle dynamics.
• Derivation of formulas for anomalous thermal Hall conductivity based on order parameter winding number and impurity potential structure.

Main Results:

• Impurities induce a significant zero-field anomalous thermal Hall conductivity, exceeding edge contributions.
• This anomalous conductivity arises from branch-conversion scattering of quasiparticles by the chiral order parameter.
• The magnitude of the anomalous thermal Hall conductivity is quantitatively linked to the impurity potential and the winding number of the chiral order parameter.

Conclusions:

• The study provides a theoretical framework for understanding impurity-induced anomalous thermal Hall conductivity in chiral superconductors.
• The findings offer a method to experimentally probe the broken time-reversal (T) and parity (P) symmetries and order parameter topology in these materials.