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arXiv · 2103.07481

Transitions in entanglement complexity in random quantum circuits by measurements

Salvatore F. E. Oliviero·Lorenzo Leone·Alioscia Hamma
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Abstract

Random Clifford circuits doped with non Clifford gates exhibit transitions to universal entanglement spectrum statistics[1] and quantum chaotic behavior. In [2] we proved that the injection of $O(n)$ non Clifford gates into a $n$-qubit Clifford circuit drives the transition towards the universal value of the purity fluctuations. In this paper, we show that doping a Clifford circuit with $O(n)$ single qubit non Clifford measurements is both necessary and sufficient to drive the transition to universal fluctuations of the purity.

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Salvatore F. E. Oliviero, Lorenzo Leone, Alioscia Hamma. 2021-03-12. Transitions in entanglement complexity in random quantum circuits by measurements. https://doi.org/10.1016/j.physleta.2021.127721

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