Evidence for a floating phase of the transverse ANNNI model at high frustration

TL;DR

This paper uses DMRG to map the phase diagram of the transverse ANNNI model at high frustration, providing strong evidence for a floating phase and precise critical line formulas.

Contribution

It offers the first detailed phase diagram of the high-frustration transverse ANNNI model, confirming the floating phase and deriving accurate critical line formulas.

Findings

Evidence for a floating phase at high frustration

Precise determination of phase boundaries

Simple formulas for critical lines

Abstract

We study the transverse quantum ANNNI model in the region of high frustration (k>0.5) using the DMRG algorithm. We obtain a precise determination of the phase diagram, showing clear evidence for the existence of a floating phase, separated from the paramagnetic modulated phase by a high-order critical line ending at the multicritical point. We obtain simple and accurate formulae for the two critical lines.