Volume 81, Number 5, March 2008
Article Number 57004
Number of page(s) 6
Section Condensed Matter: Electronic Structure, Electrical, Magnetic and Optical Properties
Published online 04 February 2008
EPL, 81 (2008) 57004
DOI: 10.1209/0295-5075/81/57004

Multiferroicity due to nonstoichiometry in the chain cuprate LiVCuO4

A. S. Moskvin1 and S.-L. Drechsler2

1  Ural State University - 620083 Ekaterinburg, Russia
2  Leibniz Institut für Festkörper- und Werkstoffforschung Dresden - D-01171, Dresden, Germany

received 6 August 2007; accepted in final form 1 January 2008; published March 2008
published online 4 February 2008

The recently observed multiferroic behavior in the s = 1/2 chain cuprate LiVCuO4 ($\equiv$ LiCuVO4) with edge-shared CuO4 plaquettes and helical spin ordering does not agree with the existing theories such as a spin-current scenario. We argue that the effect can be consistently explained, if the exchange-induced electric polarization on the out-of-chain Cu2+ centers substituting for Li ions in LiVCuO4 is taken into account. These substituent centers are proved to be an effective probe of the spin incommensurability and the magnetic-field effects.

74.72.-h - Cuprate superconductors (high-Tc and insulating parent compounds).
75.10.Pq - Spin chain models.
77.80.-e - Ferroelectricity and antiferroelectricity.

© EPLA 2008