Cumulant expansion for ferrimagnetic spin(S1,s2)systems
نویسندگان
چکیده
منابع مشابه
Cumulant expansion for systems with large spins
– A method is proposed for obtaining a systematic expansion of thermodynamic functions of spin systems with large spin S in powers of 1/S. It uses the cumulant technique and a coherent-state representation of the partition function Z. The expansion of Z in terms of cumulants yields an effective classical Hamiltonian with temperature-dependent quantum corrections. For the Heisenberg quantum Hami...
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Low-order equal-time statistics of a barotropic flow on a rotating sphere are investigated. The flow is driven by linear relaxation toward an unstable zonal jet. For relatively short relaxation times, the flow is dominated by critical-layer waves. For sufficiently long relaxation times, the flow is turbulent. Statistics obtained from a second-order cumulant expansion are compared to those accum...
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ژورنال
عنوان ژورنال: Physical Review B
سال: 2004
ISSN: 1098-0121,1550-235X
DOI: 10.1103/physrevb.70.184416