Spin nematic order in multiple-spin exchange models on the triangular lattice

TL;DR

This paper reveals that a multiple-spin exchange model on a triangular lattice exhibits an octahedral spin nematic ground state, which transforms under magnetic fields and shows a magnetization plateau, providing insights into quantum magnetic orderings.

Contribution

It identifies a novel octahedral spin nematic order in the ground state of a multiple-spin exchange model on a triangular lattice, expanding understanding of quantum magnetic phases.

Findings

Ground state has octahedral spin nematic order.

Magnetic field induces antiferro-quadrupolar order with broken Z3 symmetry.

System exhibits a magnetization plateau at half saturation.

Abstract

We figure out that the ground state of a multiple-spin exchange model applicable to thin films of solid 3He possesses an octahedral spin nematic order. In the presence of magnetic field, it is deformed into an antiferro-quadrupolar order in the perpendicular spin plane, in which lattice Z3 rotational symmetry is also broken. Furthermore, this system shows a narrow magnetization plateau at half, m/m_{sat}=1/2, which resembles recent magnetization measurement [H. Nema et al., Phys. Rev. Lett. 102, 075301 (2009)].