Nonrelativistic Multiferroicity in the Nonstoichiometric Spin s=1/2 Spiral Chain Cuprate LiCu2O2

TL;DR

This paper explains the multiferroic behavior in LiCu2O2 through nonrelativistic exchange-induced polarization, highlighting the role of Cu2+ substituents as probes of spin incommensurability and magnetic effects.

Contribution

It introduces a nonrelativistic mechanism for multiferroicity in a spin-1/2 chain cuprate, emphasizing the role of Cu2+ substituents in explaining experimental observations.

Findings

Nonrelativistic exchange-induced electric polarization explains multiferroicity.

Cu2+ substituents serve as effective probes of spin incommensurability.

Magnetic field effects are linked to substituent centers.

Abstract

We argue for a recently observed puzzling multiferroic behavior in s=1/2 1D chain cuprate LiCu2O2 with edge-shared arrangement of CuO4 plaquettes and incommensurate spiral spin ordering can be consistently explained if one takes into account the nonrelativistic exchange-induced electric polarization on the Cu2+ centers substituting for the positions native for the Cu1+ ions. These substituent centers are proved to be an effective probe of the spin incommensurability and magnetic field effects.