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arXiv · 2010.02196

Measurement-induced phase transitions in quantum automaton circuits

Jason Iaconis·Andrew Lucas·Xiao Chen
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Abstract

We study the entanglement dynamics in a generic quantum automaton circuit subjected to projective measurements. We design an efficient algorithm which not only allows us to perform large scale simulation for the Rényi entropy but also provides a physical picture for the entanglement dynamics, which can be interpreted in terms of a classical bit-string model which belongs to the directed percolation universality class. We study the purification dynamics of a state formed by EPR pairs, and the growth of entanglement starting from a product state. In both cases, we verify numerically that the dynamics is in the universality class of classical directed percolation.

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Jason Iaconis, Andrew Lucas, Xiao Chen. 2021-01-06. Measurement-induced phase transitions in quantum automaton circuits. https://doi.org/10.1103/physrevb.102.224311

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