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arXiv · quant-ph/0701077

Fidelity, dynamic structure factor, and susceptibility in critical phenomena

Wen-Long You·Ying-Wai Li·Shi-Jian Gu
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Abstract

Motivated by the growing importance of fidelity in quantum critical phenomena, we establish a general relation between fidelity and structure factor of the driving term in a Hamiltonian through a newly introduced concept: fidelity susceptibility. Our discovery, as shown by some examples, facilitates the evaluation of fidelity in terms of susceptibility using well developed techniques such as density matrix renormalization group for the ground state, or Monte Carlo simulations for the states in thermal equilibrium.

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Wen-Long You, Ying-Wai Li, Shi-Jian Gu. 2007-06-21. Fidelity, dynamic structure factor, and susceptibility in critical phenomena. https://doi.org/10.1103/physreve.76.022101

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