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Fidelity susceptibility in Gaussian Random Ensembles

Disordered Systems and Neural Networks 2020-04-10 v2 Statistical Mechanics Mathematical Physics math.MP Quantum Physics

Abstract

The fidelity susceptibility measures sensitivity of eigenstates to a change of an external parameter. It has been fruitfully used to pin down quantum phase transitions when applied to ground states (with extensions to thermal states). Here we propose to use the fidelity susceptibility as a useful dimensionless measure for complex quantum systems. We find analytically the fidelity susceptibility distributions for Gaussian orthogonal and unitary universality classes for arbitrary system size. The results are verified by a comparison with numerical data.

Keywords

Cite

@article{arxiv.1812.04853,
  title  = {Fidelity susceptibility in Gaussian Random Ensembles},
  author = {Piotr Sierant and Artur Maksymov and Marek Kuś and Jakub Zakrzewski},
  journal= {arXiv preprint arXiv:1812.04853},
  year   = {2020}
}

Comments

2nd version, 5+5pp, comments welcome

R2 v1 2026-06-23T06:39:56.770Z