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arXiv · 1209.0072

Sudden quenching in the Kitaev honeycomb model: Study of defect and heat generation

Abstract

We study the behavior of the defect and heat densities under sudden quenching near the quantum critical points in the two-dimensional Kitaev honeycomb model both in the thermodynamic and non-thermodynamic limits. We consider quenches starting from a quantum critical point into the gapped as well as the gapless phases. We choose points on the lines of anisotropic quantum critical points as well as different points of intersection of these lines as the initial points from where the quenching starts. We find that the defect and heat densities display the expected power-law scalings along with logarithmic corrections to scaling (or cusp singularities) in certain cases. In the vicinity of some of the intersection points the scaling behaviors change, indicating an effective dimensional reduction; the scaling behavior near these points depends on the number of critical lines crossed in the process of quenching. All the analytical predictions are also verified by numerical integration.

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BibTeXRIS

Aavishkar A. Patel, Amit Dutta. 2012-09-01. Sudden quenching in the Kitaev honeycomb model: Study of defect and heat generation. https://doi.org/10.1103/physrevb.86.174306

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