Universality and Scaling Properties of Correlation Functions Near a Quantum Phase Transition

R. Jafari

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arXiv · 1101.2354

Universality and Scaling Properties of Correlation Functions Near a Quantum Phase Transition

R. Jafari

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Abstract

In this paper we investigate the universality and scaling properties of the well-known quantities in classical statistical mechanics near the quantum phase transition point. We show that transverse susceptibility and derivatives of correlation functions with respect to the parameter that drives the quantum phase transitions, exhibit logarithmic divergence and finite size scaling the same as entanglement. In other words the non-analytic and finite size scaling behaviors of entanglement is not its intrinsic properties and inherit from the non-analytic and scaling behaviors of correlation functions and surveying at least the nearest neighbor correlation functions could specify the scaling and divergence properties of entanglement. However we show that the correlation functions could capture the quantum critical point without pre-assumed order parameters even for the cases where the two-body entanglement is absent.

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R. Jafari. 2011-02-11. Universality and Scaling Properties of Correlation Functions Near a Quantum Phase Transition. https://arxiv.org/abs/1101.2354

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