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arXiv · 1204.3023

Extremal spacings between eigenphases of random unitary matrices and their tensor products

Marek Smaczynski·Tomasz Tkocz·Marek Kus·Karol Zyczkowski
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Abstract

Extremal spacings between eigenvalues of random unitary matrices of size N pertaining to circular ensembles are investigated. Explicit probability distributions for the minimal spacing for various ensembles are derived for N = 4. We study ensembles of tensor product of k random unitary matrices of size n which describe independent evolution of a composite quantum system consisting of k subsystems. In the asymptotic case, as the total dimension N = n^k becomes large, the nearest neighbor distribution P(s) becomes Poissonian, but statistics of extreme spacings P(s_min) and P(s_max) reveal certain deviations from the Poissonian behavior.

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Marek Smaczynski, Tomasz Tkocz, Marek Kus, Karol Zyczkowski. 2013-06-11. Extremal spacings between eigenphases of random unitary matrices and their tensor products. https://doi.org/10.1103/physreve.88.052902

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