THOULESS NUMBER AND SPIN DIFFUSION IN QUANTUM HEISENBERG FERROMAGNETS
نویسندگان
چکیده
منابع مشابه
Thouless Number and Spin Diffusion in Quantum Heisenberg Ferromagnets
Using an analogy between the conductivity tensor of electronic systems and the spin stiffness tensor of spin systems, we introduce the concept of the Thouless number g0 and the dimensionless frequency dependent conductance g(ω) for quantum spin models. It is shown that spin diffusion implies the vanishing of the Drude peak of g(ω), and that the spin diffusion coefficient Ds is proportional to g...
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ژورنال
عنوان ژورنال: Modern Physics Letters B
سال: 1993
ISSN: 0217-9849,1793-6640
DOI: 10.1142/s0217984993001788