Auto-correlation Functions and Quantum Fluctuations of the Transverse Ising Chain by the Quantum Transfer Matrix Method

Makoto Inoue

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arXiv · 1009.0066

Auto-correlation Functions and Quantum Fluctuations of the Transverse Ising Chain by the Quantum Transfer Matrix Method

Makoto Inoue

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Abstract

The Quantum Transfer Matrix method based on the Suzuki-Trotter formulation is extended to dynamical problems. The auto-correlation functions of the Transverse Ising chain are derived by this method. It is shown that the Trotter-directional correlation function is interpreted as a Matsubara's temperature Green function and that the auto-correlation function is given by analytic continuation of the Green function. We propose the Trotter-directional correlation function is a new measure of the quantum fluctuation and show how it works well as a demonstration.

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Makoto Inoue. 2010-09-01. Auto-correlation Functions and Quantum Fluctuations of the Transverse Ising Chain by the Quantum Transfer Matrix Method. https://arxiv.org/abs/1009.0066

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