Magnetic Phase Diagram of Frustrated Spin Ladder

TL;DR

This paper maps the magnetic phase diagram of frustrated spin ladders, revealing how frustration and magnetic fields induce various magnetization plateaux and alter quasi-particle behaviors.

Contribution

First detailed magnetic phase diagram of frustrated spin ladders using variational matrix-product state method.

Findings

Multiple magnetization plateaux induced by frustration.

Frustration affects the kinetic energy of triplet and singlet quasi-particles.

Phase boundaries accurately determined.

Abstract

Frustrated spin ladders show magnetization plateaux depending on the rung-exchange interaction and frustration defined by the ratio of first and second neighbor exchange interactions in each chain. This paper is the first report on its magnetic phase diagram. Using the variational matrix-product state method, we accurately determine phase boundaries. Several kinds of magnetization plateaux are induced by the frustration and the strong correlation among quasi-particles on a lattice. The appropriate description of quasi-particles and their relevant interactions are changed by a magnetic field. We find that the frustration differentiates the triplet quasi-particle from the singlet one in kinetic energy.