title: Magnetic ground state and transition of a quantum multiferroic LiCu2O2.
abstract: Based on resonant soft x-ray magnetic scattering, we report that LiCu2O2 exhibits a large interchain coupling which suppresses quantum fluctuations along spin chains, and a quasi-2D short-range magnetic order prevails at temperatures above the magnetic transition. These observations unravel the fact that the ground state of LiCu2O2 possesses long-range 2D-like incommensurate magnetic order rather than being a gapped spin liquid as expected from the nature of quantum spin-1/2 chains. In addition, the spin coupling along the c axis is found to be essential for inducing electric polarization.
authors.affiliation: National Synchrotron Radiation Research Center, Hsinchu 30076, Taiwan.
authors.forename: S W
authors.initials: SW
authors.lastname: Huang
authors.forename: D J
authors.initials: DJ
authors.lastname: Huang
authors.forename: J
authors.initials: J
authors.lastname: Okamoto
authors.forename: C Y
authors.initials: CY
authors.lastname: Mou
authors.forename: W B
authors.initials: WB
authors.lastname: Wu
authors.forename: K W
authors.initials: KW
authors.lastname: Yeh
authors.forename: C L
authors.initials: CL
authors.lastname: Chen
authors.forename: M K
authors.initials: MK
authors.lastname: Wu
authors.forename: H C
authors.initials: HC
authors.lastname: Hsu
authors.forename: F C
authors.initials: FC
authors.lastname: Chou
authors.forename: C T
authors.initials: CT
authors.lastname: Chen