Spin dynamics in S=1/2 chains with next-nearest-neighbor exchange interactions

Article

关键词: PEIERLS TRANSITION;    HEISENBERG CHAIN;    PHASE-TRANSITION;    CRITICAL-POINT;    RESONANCE;    MAGNETIZATION;    MAGNETISM;    DIMER;   

DOI  :  10.1103/PhysRevB.82.014416

来源: SCIE

【 摘 要 】

Low-energy magnetic excitations in the S = 1/2 chain compound [(C6H9N2)CuCl3]CuCl3 [known as (6MAP)CuCl3] are probed by means of tunable-frequency electron spin resonance. Two modes with asymmetric (with respect to the hv = g mu B-B line) frequency-field dependences are resolved, illuminating the striking incompatibility with a simple uniform S = 1/2 Heisenberg chain model. The unusual ESR spectrum is explained in terms of the recently developed theory for S = 1/2 chains, suggesting the important role of next-nearestneighbor interactions in this compound. Our conclusion is supported by model calculations for the magnetic susceptibility of (6MAP)CuCl3, revealing a good qualitative agreement with experiment.

【 授权许可】

Free