Nernst effect anisotropy as a sensitive probe of Fermi surface distortions from electron-nematic order

TL;DR

This paper demonstrates that the anisotropy of the Nernst effect in layered metals is a highly sensitive indicator of Fermi surface distortions caused by electron-nematic order, especially near van-Hove singularities.

Contribution

It introduces the Nernst effect anisotropy as a novel, highly sensitive probe for detecting electron-nematic order in layered metals.

Findings

Nernst anisotropy effectively detects Fermi surface distortions.

Enhanced sensitivity near van-Hove singularities.

Supports the presence of electron-nematic order in YBCO.

Abstract

We analyze the thermoelectric response in layered metals with spontaneously broken rotation symmetry. We identify the anisotropy of the quasiparticle Nernst signal as an extremely sensitive probe of Fermi surface distortions characteristic of the ordered state. This is due to a subtle interplay of different transport anisotropies which become additionally enhanced near van-Hove singularities. Applied to recent experiments, our results reinforce the proposal that the underdoped cuprate superconductor YBCO displays such ``electron-nematic'' order in the pseudogap regime.