Parisi-Symmetry of the Many-Body Quantum Theory of randomly interacting fermionic systems

TL;DR

This paper demonstrates how fermionic systems with random interactions exhibit Parisi replica symmetry breaking, affecting their low-temperature quantum properties, excitations, and phase diagrams, with implications for metallic and superconducting spin glasses.

Contribution

It introduces a new Green's function representation linking fermionic spin glasses to Hubbard models and explores the effects of RPSB on quantum correlations and phase transitions.

Findings

RPSB strongly influences low-energy excitations and dynamics.

A new Green's function representation maps spin glasses to Hubbard models.

RPSB effects impact phase diagrams and ground state transitions.

Abstract

We show that fermion systems with random interactions lead to strong coupling of glassy order and fermionic correlations, which culminates in the implementation of Parisi replica permutation symmetry breaking (RPSB) in their T=0 quantum field theories. Precursor effects below fermionic AT-lines become stronger as the temperature decreases and play a crucial role within the entire low T regime. The Parisi ultrametric structure is shown to determine low energy excitations and the dynamic behaviour of fermionic correlations for large times, which is predicted to affect transport properties in metallic (and superconducting) spin glasses. Thus we reveal quantum dynamical fingerprints of the Parisi scheme. These effects, being strongest as T->0, are contrasted with quantum spin glass transitions at T=0 displaying only small RPSB corrections at low T. RPSB-effects moreover appear to influence the loci of the ground state transitions at O(T^0) and hence the phase diagrams. We derive a new representation of the T=0 Green's function which leads to a map of the fermionic (insulating) spin glass solution to the local limit solution of a Hubbard model with a random repulsive interaction. We obtain the distribution of the Hubbard interaction fluctuation and its dependence on the order of RPSB. A generalized mapping between metallic spin glass and random U Hubbard model is conjectured. The new representation of the Green's function at T=0 is suggested to be useful for generalizations to superconductors with spin glass phases.