Hidden Symmetry and Mutiferroicity in a Triangular Spin Lattice With Proper-Screw-Spin Chain Order

TL;DR

This study investigates multiferroicity in a triangular spin lattice with proper-screw-spin chains, revealing how hidden symmetry and spin frustration contribute to ferroelectric polarization.

Contribution

It provides a detailed analysis of the symmetry and magnetic structure in AgCrO2, highlighting the role of hidden symmetry in multiferroic behavior.

Findings

Strong geometric spin frustration in the lattice

Ferroelectric polarization from spiral-spin chain structures

Polarization aligned with mirror plane due to hidden symmetry

Abstract

The multiferroicity in a triangular spin lattice with proper-screw-spin chain order was explored by performing density functional calculations for AgCrO2 and analyzing the symmetry of the magnetic structure of the triangular spin lattice. Strong geometric spin frustration exists within and between CrO2 layers, and the ferroelectric polarization originates from the spiral-spin chain structures propagating across the proper-screw-spin chains. The triangular spin lattice can have ferroelectric polarization parallel to its mirror plane due to hidden symmetry.