Tricritical behaviour of Ising spin glasses with charge fluctuations

TL;DR

This paper investigates tricritical points in fermionic Ising spin glasses, revealing their existence at specific chemical potentials or fillings, with exact and renormalization group analyses, and draws parallels with zero-temperature quantum spin glass transitions.

Contribution

It provides the first detailed analysis of tricritical behaviour in fermionic Ising spin glasses, including exact solutions and renormalization group insights, highlighting novel quantum critical phenomena.

Findings

Existence of tricritical points at specific chemical potentials or fillings.

Exact solutions for infinite-range interactions.

Identification of a new zero-temperature tricritical point in quantum spin glasses.

Abstract

We show that tricritical points displaying unusal behaviour exist in phase diagrams of fermionic Ising spin glasses as the chemical potential or the filling assumes characteristic values. Exact results for infinite range interaction and a one loop renormalization group analysis of thermal tricritical fluctuations for finite range models are presented. Surprising similarities with zero temperature transitions and a new $T=0$ tricritical point of metallic quantum spin glasses are derived.