Experimental evidence for Shekhtman-Entin-Wohlman-Aharony (SEA) interactions in Ba2CuGe2O7

TL;DR

This study provides experimental evidence that Shekhtman-Entin-Wohlman-Aharony (SEA) interactions significantly influence the magnetic properties of Ba2CuGe2O7, refining the understanding of its spin structure beyond previous models.

Contribution

The paper demonstrates the first clear experimental evidence of SEA interactions affecting magnetic behavior in a real insulator, refining the magnetic model of Ba2CuGe2O7.

Findings

SEA interactions explain deviations from the ideal sinusoidal spin spiral

Experimental data aligns with models including SEA terms

First direct evidence of SEA effects in a magnetic insulator

Abstract

New neutron diffraction and inelastic neutron scattering experiments on Ba2CuGe2O7 suggest that the previously suggested model for the magnetism of this material (an ideal sinusoidal spin spiral, stabilized by isotropic exchange and Dzyaloshinskii-Moriya interactions) needs to be refined. Both new and previously published experimental results can be quantitatively explained by taking into account the Shekhtman-Entin-Wohlman-Aharony (SEA) term, a special anisotropy term that was predicted to always accompany Dzyaloshinskii-Moriya interactions in insulators. Our experimental results present the first clear evidence to that SEA interactions can lead to substantial observable effects in a real magnetic system.