Transverse thermoelectric transport in a model of many competing order parameters

TL;DR

This paper models the transverse thermoelectric transport in systems with multiple competing orders, revealing how order parameter fluctuations contribute to the Nernst signal at high temperatures.

Contribution

It introduces a non-linear sigma model approach to analyze competing orders and calculates the transverse thermoelectric response in the large N limit.

Findings

Order parameter fluctuations significantly influence the Nernst signal.

Results are consistent with Gaussian fluctuation models for superconductivity.

Applicable to high-temperature regimes with multiple competing orders.

Abstract

Coexisting fluctuations towards various ordered states are ubiquitous in strongly correlated electronic systems. In particular, measurements of underdoped cuprate high-temperature superconductors reveal evidence for short range charge order in parallel to large superconducting fluctuations. Here we use a non-linear sigma model to describe a system with N competing orders, and calculate its transverse thermoelectric transport coefficient in the analytically tractable limit of large N . Our results, which determine the contribution of order parameter fluctuations to the Nernst signal, are appropriate for high temperatures in the case of finite N . They are similar to previously obtained results within a model of Gaussian superconducting fluctuations.