The Fracton quantum gas

TL;DR

This paper develops a linear-response theory for a fracton quantum gas derived from a dipole-conserving Hamiltonian, including density operator construction and plasmon dispersion calculation.

Contribution

It introduces a quantisation framework for fracton gases and derives their linear-response functions and collective excitation spectra.

Findings

Density-density response function derived in large-flavor limit

Fracton-plasmon dispersion relation calculated

Consistent density operator construction established

Abstract

Starting from a simple dipole-conserving Hamiltonian model, after introducing a proper quantisation framework, we construct the linear-response theory of a fracton quantum gas. We show how to consistently construct the density operator and we calculate the density-density linear-response function in the limit of large number of (fracton) flavours. We show how to construct its random-phase approximation, from which we calculate the fracton-plasmon dispersion.