Thermal Hall conductivity in the spin-triplet superconductor with broken time-reversal symmetry

Abstract

Motivated by the spin-triplet superconductor Sr2RuO4, the thermal Hall conductivity is investigated for several pairing symmetries with broken time-reversal symmetry. In the chiral p-wave phase with a fully opened quasiparticle excitation gap, the temperature dependence of the thermal Hall conductivity has a temperature linear term associated with the topological property directly, and an exponential term, which shows a drastic change around the Lifshitz transition. Examining f -wave states as alternative candidates with d = ∆0ẑ(k 2 x − k 2 y )(kx ± iky) and d = ∆0ẑkxky(kx ± iky) with gapless quasiparticle excitations, we study the temperature dependence of the thermal Hall conductivity, where for the former state the thermal Hall conductivity has a quadratic dependence on temperature, originating from the linear dispersions, in addition to linear and exponential behavior. The obtained result may enable us to distinguish between the chiral p-wave and f -wave states in Sr2RuO4.

Topological Superconductivity Induced by Magnetic Texture Crystals

“…Chiral and (quasi-)helical MFs have instead a fixed spin character, since they stem from fully-gapped TSCs. Even more, the various dispersionless or dispersive Majorana and Andreev edge modes can be probed in suitably-designed generally-spin-resolved charge and thermal transport experiments [229][230][231][232][233]. Depending on whether we have electrically neutral (Majorana) or charged (Andreev) edge excitations one can correspondingly look for characteristic features and scaling behaviors in thermal and Hall responses [233].…”

Odd-Parity Spin-Triplet Superconductivity in Centrosymmetric Antiferromagnetic Metals

“…Thus, the Case (ii) O-AFM superconducting state can be interpreted as a mirror Chern superconductor, whose M z = ±1 eigensectors are analogous to chiral p-wave superconductors with the Chern number ±1 [52]. In Case (i) or (iii) with a nonzero Chern number, the thermal Hall conductance and the spin Nernst conductance are quantized due to the spin-polarized edge channels [61]. In Case (ii), although the net thermal Hall conductivity vanishes, we expect a finite spin Nernst conductance, since the edge quasiparticles with opposite spins propagate in opposite directions.…”

Spontaneous thermal Hall conductance in superconductors with broken time-reversal symmetry

“…THCs can spontaneously become non-zero for TRS broken SCs. Though the non-zero THCs can have a contribution from topologically protected edge states [27][28][29][30], here we investigate an additional effect, the impurity mechanism (IM) for κ yx [4,31].…”