Simulated nuclear spin-lattice relaxation in Heisenberg ferrimagnets: Indirect observation of quadratic dispersion relations

Article

关键词: MAGNETIC-PROPERTIES;    LOW-TEMPERATURE;    CHAINS;    DYNAMICS;    SYSTEMS;    STATES;    MODEL;   

DOI  :  10.1103/PhysRevB.61.R842

来源: SCIE

【 摘 要 】

In response to recent proton spin-relaxation time measurements on NiCu(pba)(H2O)(3). 2H(2)O with pba = 1,3-propylenebis(oxamato), which is an excellent one-dimensional ferrimagnetic Heisenberg model system of spin (1,1/2), we study the Raman relaxation process in spin-(S,s) quantum ferrimagnets on the assumption of predominantly dipolar hyperfine interactions between protons and magnetic ions. The relaxation time T-1 is formulated within the spin-wave theory and is estimated as a function of temperature and an applied field H by a quantum Monte Carlo method. The low-temperature behavior of the relaxation rate T-1(-1) qualitatively varies with (S,s), while T-1(-1) is almost proportional to H-1/2 due to the characteristic dispersion relations.

【 授权许可】

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