Nonlinear valley thermal physics in two dimensional materials

TL;DR

This paper explores nonlinear valley thermal effects in 2D materials driven by quantum metric, revealing valley-specific thermoelectric corrections to orbital magnetization and their dependence on material parameters, with implications for valleytronics.

Contribution

It introduces a novel understanding of nonlinear valley thermal effects linked to quantum metric and demonstrates how material parameters influence these effects in 2D systems.

Findings

Valley indices are distinguishable by thermoelectric correction to orbital magnetization.

Nonlinear valley thermal response depends on intrinsic material parameters.

Implications for valleytronics and valley caloritonics are discussed.

Abstract

This study delves into the intrinsic nonlinear valley thermal effects, driven by the Quantum Metric of the system. Our findings elucidate that valley indices in the nonlinear effect are distinguishable by the thermoelectric correction to the orbital magnetization, which adopts opposite signs across valleys mirroring the role of orbital angular momentum in the linear valley Hall effect. Through a prototypical two-band model on an anisotropic tilted Dirac semimetal, we investigate how intrinsic material parameters modulate this nonlinear valley thermal response. Extending to realistic PT symmetric anisotropic semiconductors, our findings enrich the understanding of valley-based phenomena, with implications for advanced theoretical and experimental pursuits in valleytronics and valley caloritonics.