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arXiv · 0803.2940

Operator fidelity susceptibility: an indicator of quantum criticality

Xiaoguang Wang·Zhe Sun·Z. D. Wang
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Abstract

We introduce the operator fidelity and propose to use its susceptibility for characterizing the sensitivity of quantum systems to perturbations. Two typical models are addressed: one is the transverse Ising model exhibiting a quantum phase transition, and the other is the one dimensional Heisenberg spin chain with next-nearest-neighbor interactions, which has the degeneracy. It is revealed that the operator fidelity susceptibility is a good indicator of quantum criticality regardless of the system degeneracy.

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Xiaoguang Wang, Zhe Sun, Z. D. Wang. 2008-03-20. Operator fidelity susceptibility: an indicator of quantum criticality. https://doi.org/10.1103/physreva.79.012105

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