Interference of nematic quantum critical quasiparticles: a route to the octet model

TL;DR

This paper proposes that nematic quantum critical fluctuations, combined with velocity anisotropy, explain the unusual coherence accumulation at specific momentum points observed in cuprate superconductors, shedding light on quasiparticle interference phenomena.

Contribution

It introduces a novel mechanism involving nematic quantum critical fluctuations and velocity anisotropy to explain quasiparticle coherence patterns in superconductors.

Findings

Nematic quantum critical fluctuations contribute to quasiparticle coherence.

Velocity anisotropy plays a key role in coherence accumulation.

The mechanism explains the octet model in cuprate superconductors.

Abstract

Repeated observations of inhomogeneity in cuperate superconductors[1-5] make one immediately question the existance of coherent quasiparticles(qp's) and the applicability of a momentum space picture. Yet, obversations of interference effects[6-9] suggest that the qp's maintain a remarkable coherence under special circumstances. In particular, quasi-particle interference (QPI) imaging using scanning tunneling spectroscopy revealed a highly unusual form of coherence: accumulation of coherence only at special points in momentum space with a particular energy dispersion[5-7]. Here we show that nematic quantum critical fluctuations[10], combined with the known extreme velocity anisotropy[11] provide a natural mechanism for the accumulation of coherence at those special points. Our results raise the intriguing question of whether the nematic fluctuations provide the unique mechanism for such a phenomenon.