Publications Repository - Helmholtz-Zentrum Dresden-Rossendorf

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

Ozerov, M.; Zvyagin, A. A.; Cizmár, E.; Wosnitza, J.; Feyerherm, R.; Xiao, F.; Landee, C. P.; Zvyagin, S. A.

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 hnu =gµBB 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-nearest-neighbor 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

  • Physical Review B 82(2010), 014416

Publ.-Id: 14330