NMR relaxation in the spin-1 Heisenberg chain

Article

关键词: NUCLEAR MAGNETIC-RELAXATION;    HALDANE-GAP SYSTEM;    RENORMALIZATION-GROUP;    LADDER (VO)(2)P2O7;    STATIC PROPERTIES;    SIGMA-MODEL;    HIGH-FIELD;    DIFFUSION;    DYNAMICS;    TEMPERATURE;   

DOI  :  10.1103/PhysRevB.100.094411

来源: SCIE

【 摘 要 】

We consider the isotropic S = 1 Heisenberg chain with a finite Haldane gap Delta and use state-of-the-art numerical techniques to investigate its dynamical properties at finite temperature, focusing on the nuclear spin-lattice relaxation rate 1/T-1 measured in nuclear magnetic resonance (NMR) experiments, for instance. In particular, we analyze the contributions from modes with momenta close to q approximate to 0 and q approximate to pi as a function of temperature. At high-temperature we observe spin diffusion, while at low-temperature we argue that a simple activated behavior 1/T-1 proportional to exp(-Delta/T) can be observed only at temperatures much smaller than the gap Delta.

【 授权许可】

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