Magnetization Plateaus in a Solvable 3-Leg Spin Ladder

TL;DR

This paper introduces an exactly solvable 3-leg spin ladder model exhibiting fractional magnetization plateaus, with detailed phase diagrams and susceptibility behavior, aligning well with previous numerical and perturbative findings.

Contribution

The authors develop a solvable spin ladder model with fractional magnetization plateaus and derive its phase diagram analytically for all coupling and magnetic field values.

Findings

Magnetization plateaus occur at fractional values of total magnetization.

The phase diagram can be exactly calculated for all rung couplings and magnetic fields.

Susceptibility shows anomalous behavior near plateau boundaries.

Abstract

We present a solvable ladder model which displays magnetization plateaus at fractional values of the total magnetization. Plateau signatures are also shown to exist along special lines. The model has isotropic Heisenberg interactions with additional many-body terms. The phase diagram can be calculated exactly for all values of the rung coupling and the magnetic field. We also derive the anomalous behaviour of the susceptibility near the plateau boundaries. There is good agreement with the phase diagram obtained recently for the pure Heisenberg ladders by numerical and perturbative techniques.