Phase diagram of weakly coupled Heisenberg spin chains subject to a uniform Dzyaloshinskii-Moriya interaction

Article

关键词: ANISOTROPIC SUPEREXCHANGE INTERACTION;    QUANTUM;    EXCHANGE;    DYNAMICS;   

DOI  :  10.1103/PhysRevB.95.214404

来源: SCIE

【 摘 要 】

Motivated by recent experiments on spin chain materials K2CuSO4Cl2 and K2CuSO4Br2, we theoretically investigate the problem of weakly coupled spin chains (chain exchange J, interchain J') subject to a staggered between chains, but uniform within a given chain, Dzyaloshinskii-Moriya (DM) interaction of magnitude D. In the experimentally relevant limit J' << D << J of the strong DM interaction the spins on the neighboring chains are forced to rotate in opposite directions, effectively resulting in a cancellation of the interchain interaction between components of spins in the plane normal to the vector D. This has the effect of promoting a two-dimensional collinear spin density wave state, which preserves U(1) symmetry of rotations about the D axis. We also investigate response of this interesting system to an external magnetic field h and obtain the h-D phase diagrams for the two important configurations h vertical bar vertical bar D and h perpendicular to D.

【 授权许可】

Free