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International Journal of Modern Physics B

NOVEL PATH INTEGRAL APPROACH TO EFFECTIVE FIELD THEORIES FOR D-DIMENSIONAL QUANTUM SPIN SYSTEMS

Antimo Angelucci, Giancarlo Jug

Published Jul 1, 1989• 15 citations
Publisher

Abstract

We present a novel path integral formulation for the effective field theory describing d-dimensional quantum spin models. The new approach avoids the coherent states representation, but at very low temperatures reproduces all known results obtained with the latter technique for describing excitations of the Neél state. The possibility of exploring higher-temperature, unbroken-symmetry state excitations (such as those appropriate for the quantum spin-liquid state) within this method is illustrated.

DOI
10.1142/s0217979289000737

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