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arXiv · 1010.1048

Quantum fidelity in the thermodynamic limit

Marek M. Rams·Bogdan Damski
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Abstract

We study quantum fidelity, the overlap between two ground states of a many-body system, focusing on the thermodynamic regime. We show how drop of fidelity near a critical point encodes universal information about a quantum phase transition. Our general scaling results are illustrated in the quantum Ising chain for which a remarkably simple expression for fidelity is found.

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Marek M. Rams, Bogdan Damski. 2011-02-07. Quantum fidelity in the thermodynamic limit. https://doi.org/10.1103/physrevlett.106.055701

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