کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
5407867 1393240 2006 9 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Magnetization and spin-spin energy diffusion in the XY model: A diagrammatic approach
موضوعات مرتبط
مهندسی و علوم پایه شیمی شیمی تئوریک و عملی
پیش نمایش صفحه اول مقاله
Magnetization and spin-spin energy diffusion in the XY model: A diagrammatic approach
چکیده انگلیسی
It is shown that the diagrammatic cluster expansion technique for equilibrium averages of spin operators may be straightforwardly extended to the calculation of time-dependent correlation functions of spin operators. We use this technique to calculate exactly the first two non-vanishing moments of the spin-spin and energy-energy correlation functions of the XY model with arbitrary couplings, in the long-wavelength, infinite temperature limit appropriate for spin diffusion. These moments are then used to estimate the magnetization and spin-spin energy diffusion coefficients of the model using a phenomenological theory of Redfield. Qualitative agreement is obtained with recent experiments measuring diffusion of dipolar energy in calcium fluoride.
ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Journal of Magnetic Resonance - Volume 179, Issue 1, March 2006, Pages 11-19
نویسندگان
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