Exact results for quench dynamics and defect production in a two-dimensional model

K. Sengupta; Diptiman Sen; Shreyoshi Mondal

doi:10.1103/physrevlett.100.077204

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arXiv · 0710.1712

Exact results for quench dynamics and defect production in a two-dimensional model

K. Sengupta·Diptiman Sen·Shreyoshi Mondal

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Abstract

We show that for a d-dimensional model in which a quench with a rate τ^{-1} takes the system across a d-m dimensional critical surface, the defect density scales as n \sim 1/τ^{mν/(zν+1)}, where νand z are the correlation length and dynamical critical exponents characterizing the critical surface. We explicitly demonstrate that the Kitaev model provides an example of such a scaling with d=2 and m=ν=z=1. We also provide the first example of an exact calculation of some multispin correlation functions for a two-dimensional model which can be used to determine the correlation between the defects. We suggest possible experiments to test our theory.

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K. Sengupta, Diptiman Sen, Shreyoshi Mondal. 2008-01-15. Exact results for quench dynamics and defect production in a two-dimensional model. https://doi.org/10.1103/physrevlett.100.077204

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