Magnetic phase diagrams of the spin-$\frac{1}{2}$ Heisenberg model on a kagome-strip chain: Emergence of a Haldane phase

TL;DR

This study maps the magnetic phase diagrams of a frustrated spin-1/2 kagome-strip chain, revealing fifteen magnetization-plateau phases including a Haldane phase, using advanced numerical methods.

Contribution

It provides the first comprehensive magnetic phase diagrams of the kagome-strip chain under various magnetizations, identifying a Haldane phase among the quantum ground states.

Findings

Identified fifteen magnetization-plateau phases.

Discovered a phase equivalent to the spin-1 Haldane phase.

Mapped phase diagrams at multiple magnetization ratios.

Abstract

Frustrated one-dimensional quantum spin systems are known to exhibit a variety of quantum ground states due to the effects of quantum fluctuations and frustrations. In a spin-1/2 kagome-strip chain, which is one of the frustrated one-dimensional spin systems, many quantum phases have been found. However, the magnetic phase diagrams of the kagome-strip chain under magnetic field have not been fully understood. We construct magnetic phase diagrams at 0, 1/5, 3/10, 1/3, 2/5, 7/15, 3/5, and 4/5 magnetization ratio in the kagome-strip chain and investigate magnetic properties in each phase using the density matrix renormalization group method. We find fifteen magnetization-plateau phases, one of which is equivalent to the spin-1 Haldane phase.