Spin-Fluctuation Drag Thermopower of Nearly Ferromagnetic Metals

TL;DR

This paper theoretically examines how spin fluctuations near a ferromagnetic quantum critical point influence the thermopower, revealing enhanced linear temperature behavior and quantum critical effects in nearly ferromagnetic metals.

Contribution

It introduces a theoretical model showing how spin fluctuations affect thermopower and identifies quantum critical behavior in the temperature dependence of correction terms.

Findings

Spin fluctuations enhance the linear T coefficient of thermopower.

Quantum critical behavior appears in correction terms similar to specific heat.

Theoretical explanation for anomalous low-temperature thermopower in nearly ferromagnetic metals.

Abstract

We investigate theoretically the Seebeck effect in materials close to a ferromagnetic quantum critical point to explain anomalous behaviour at low temperatures. It is found that the main effect of spin fluctuations is to enhance the coefficient of the leading $T$-linear term, and a quantum critical behaviour characterized by a spin-fluctuation temperature appears in the temperature dependence of correction terms as in the specific heat.