Spin coherent-state path integrals and the instanton calculus
نویسندگان
چکیده
منابع مشابه
N ov 2 00 1 SPIN COHERENT - STATE PATH INTEGRALS AND THE INSTANTON CALCULUS ANUPAM GARG
We use an instanton approximation to the continuous-time spin coherentstate path integral to obtain the tunnel splitting of classically degenerate ground states. We show that provided the fluctuation determinant is carefully evaluated, the path integral expression is accurate to order O(1/j). We apply the method to the LMG model and to the molecular magnet Fe8 in a transverse field. This paper ...
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It is pointed out that there are some fundamental difficulties with the frequently used continuous-time formalism of the spin-coherent-state path integral. They arise already in a single-spin system and at the level of the ”classical action” not to speak of fluctuations around the ”classical path”. Similar difficulties turn out to be present in the case of the (boson-)coherentstate path integra...
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ژورنال
عنوان ژورنال: Journal of Mathematical Physics
سال: 2003
ISSN: 0022-2488,1089-7658
DOI: 10.1063/1.1521797