arXiv subjects

Ying-Fei Zhang

Publications and source records attributed to Ying-Fei Zhang.

3 recordsLinked to original sources

arXiv2026

Anomalous Thomson Effect

We formulate an effect called the anomalous Thomson effect (ATE), which constitutes the Thom?son counterpart to the anomalous Hall effect and anomalous Nernst effect (ANE). The anomalous Thomson coefficient (ATC) is determined by the anomalous Nernst coefficient (ANC) together with the temperature dependence of both the ANC and the longitudinal electrical conductivity; This relation is model independent within local linear response and holds for the total anomalous Nernst coefficient, irrespective of whether its microscopic origin is intrinsic or extrinsic. Specifically, we study a massive Dirac model for Fe3Sn2 to capture intrinsic Berry-curvature-driven transport, where the Berry curvature near the gapped Dirac cones enhances the ANC-related contributions to the ATC, and we also deduce the ATC from measured experimental data reported for CoS2,Co3Sn2S2, and CeCrGe3. In the low-temperature limit, the ratio ATC/ANC approaches three, and we find that the ATC for CeCrGe3 can be as large as ten times the ANC in the liquid-nitrogen temperature regime, making this effect highly attractive for solid-state thermoelectric refrigeration in this temperature range. It is important to emphasize that the formulated ATE can be directly verified using existing ANE and longitudinal conductivity data, without the need for additional equipment or measurements.

cond-mat.mes-hall↗

arXiv2026

Fundamental Relations as the Leading Order in Nonlinear Thermoelectric Responses with Time-Reversal Symmetry

In recent years, nonlinear transport phenomena have garnered significant interest in both theoretical explorations and experiments. In this work, we utilize the semi-classical wave packet theory to calculate disorder-induced second-order transport coefficients: second-order electrical ($σ$), thermoelectric ($α$), and thermal ($κ$) coefficients, capturing the interplay between side-jump and skew-scattering contributions in systems with time-reversal symmetry. Using a topological insulator model, we quantitatively characterize the Fermi-level dependence of these second-order transport coefficients by explicitly including Coulomb impurity potentials. Furthermore, we elucidate the relationships between these coefficients, establishing the second-order Mott relation and the Wiedemann-Franz law induced by disorder. This study develops a comprehensive theoretical framework elucidating the nonlinear thermoelectric transport mechanisms in quantum material systems.

cond-mat.mes-hall↗

arXiv2025

The second-order intrinsic Wiedemann-Franz law

In recent years, the nonlinear anomalous thermal Hall effect has attracted substantial attention. In this paper, we carry out a theoretical exploration of the intrinsic anomalous thermal Hall and Nernst effect that is induced by the thermal Berry connection polarizability. This effect is independent of the relaxation time and can be present in antiferromagnets possessing PT symmetry. Additionally, we put forward a second-order intrinsic Wiedemann-Franz law, which represents the ratio of the second-order intrinsic thermal conductivity coefficient to the second-order intrinsic electrical conductivity coefficient . When analyzed within a four-band PT symmetric Dirac model, we observe that the second-order intrinsic thermal conductivity coefficient is linearly proportional to the second-order intrinsic electrical conductivity coefficient , and the second-order intrinsic Wiedemann-Franz law is characterized by the chemical potential $μ$ in the low-temperature regime. These findings provide significant implications for experimental verification.

cond-mat.mes-hall↗