New high magnetic field phase of the frustrated $S=1/2$ chain compound LiCuVO$_4$

TL;DR

This paper reports the experimental discovery of a new high magnetic field phase in LiCuVO$_4$, identified as a spin nematic phase, aligning with theoretical predictions and expanding understanding of frustrated quantum spin chains.

Contribution

First experimental observation of a spin nematic phase in a frustrated $S=1/2$ chain compound, confirming theoretical models.

Findings

Identification of a new magnetic phase below saturation field

Agreement of critical fields with theoretical calculations

Observation of a spin nematic phase in LiCuVO$_4$

Abstract

Magnetization of the frustrated $S=1/2$ chain compound LiCuVO$_4$, focusing on high magnetic field phases, is reported. Besides a spin-flop transition and the transition from a planar spiral to a spin modulated structure observed recently, an additional transition was observed just below the saturation field. This newly observed magnetic phase is considered as a spin nematic phase, which was predicted theoretically but was not observed experimentally. The critical fields of this phase and its dM/dH curve are in good agreement with calculations performed in a microscopic model (M. E. Zhitomirsky and H. Tsunetsugu, preprint, arXiv:1003.4096v2).