Finite-size scaling at the first-order quantum transitions of quantum Potts chains

TL;DR

This paper studies finite-size effects at first-order quantum transitions in q-state Potts chains, revealing how boundary conditions influence scaling behavior near the transition point.

Contribution

It introduces a finite-size scaling framework for first-order quantum transitions in Potts chains, emphasizing boundary condition effects.

Findings

Finite-size scaling describes low-energy properties near the transition.

Boundary conditions significantly affect the scaling variables.

Scaling ansatzes successfully characterize the transition behavior.

Abstract

We investigate finite-size effects in quantum systems at first-order quantum transitions. For this purpose we consider the one-dimensional q-state Potts models which undergo a first-order quantum transition for any q>4, separating the quantum disordered and ordered phases with a discontinuity in the energy density of the ground state. The low-energy properties around the transition show finite-size scaling, described by general scaling ansatzes with respect to appropriate scaling variables. The size dependence of the scaling variables presents a particular sensitiveness to boundary conditions, which may be considered as a peculiar feature of first-order quantum transitions.