Lightly doped La(2-x)Sr(x)CuO(4) as a Lifshitz helimagnet

TL;DR

This paper investigates the magnetic properties of lightly doped La(2-x)Sr(x)CuO(4), revealing a transition from a canted Neel state to a helicoidal magnetic phase as doping increases, using a dipolar frustration model.

Contribution

It introduces a dipolar frustration model to explain the magnetic phase transition in lightly doped La(2-x)Sr(x)CuO(4), unifying neutron scattering and Raman experiment observations.

Findings

Canted Neel state stable for x<2% due to anisotropies

Transition to helicoidal magnetic phase at higher doping

Reconciliation of neutron scattering and Raman data

Abstract

We study the static magnetic correlations in lightly doped La(2-x)Sr(x)CuO(4) within the framework of a dipolar frustration model for a canted antiferromagnet. We show that the stability of the canted Neel state for x<2% is due to the Dzyaloshinskii-Moriya and XY anisotropies. For higher doping the ground state is unstable towards a helicoidal magnetic phase where the transverse components of the staggered magnetization rotate in a plane perpendicular to the orthorhombic b-axis. Our theory reconciles, for the first time, the incommensurate peaks observed in elastic neutron scattering with Raman and magnetic susceptibility experiments in La(2-x)Sr(x)CuO(4).