Spin-Flop Phenomenon of Two-Dimensional Frustrated Antiferromagnets without Anisotropy in Spin Space

TL;DR

This paper demonstrates that the spin-flop phenomenon in isotropic two-dimensional frustrated antiferromagnets occurs across different lattice geometries, revealed through numerical diagonalization showing magnetization jumps at high fields.

Contribution

It extends the understanding of spin-flop phenomena to new lattice structures without anisotropy, using numerical methods to identify similar magnetization behaviors.

Findings

Spin-flop phenomenon observed in multiple lattice types.

Magnetization jumps occur at one-third saturation.

Phenomenon is not limited to the square-kagome lattice.

Abstract

Motivated by a recent finding of a spin-flop phenomenon in a system without anisotropy in spin space reported in the S=1/2 Heisenberg antiferromagnet on the square-kagome lattice, we study the S=1/2 Heisenberg antiferromagnets on two other lattices composed of vertex-sharing triangles by the numerical diagonalization method. One is a novel lattice including a shuriken shape with four teeth; the other is the kagome lattice with $\sqrt{3}\times\sqrt{3}$-structure distortion, which includes a shuriken shape with six teeth. We find in the magnetization processes of these systems that a magnetization jump accompanied by a spin-flop phenomenon occurs at the higher-field-side edge of the magnetization plateau at one-third the height of saturation. This finding indicates that the spin-flop phenomenon found in the isotropic system on the square-kagome lattice is not an exceptional case.