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arXiv · 2104.10451

Generalized quantum measurements with matrix product states: Entanglement phase transition and clusterization

Elmer V. H. Doggen·Yuval Gefen·Igor V. Gornyi·Alexander D. Mirlin·Dmitry G. Polyakov
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Abstract

We propose a method, based on matrix product states, for studying the time evolution of many-body quantum lattice systems under continuous and site-resolved measurement. Both the frequency and the strength of generalized measurements can be varied within our scheme, thus allowing us to explore the corresponding two-dimensional phase diagram. The method is applied to one-dimensional chains of nearest-neighbor interacting hard-core bosons. A transition from an entangling to a disentangling (area-law) phase is found. However, by resolving time-dependent density correlations in the monitored system, we find important differences between different regions at the phase boundary. In particular, we observe a peculiar phenomenon of measurement-induced particle clusterization that takes place only for frequent moderately strong measurements, but not for strong infrequent measurements.

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Elmer V. H. Doggen, Yuval Gefen, Igor V. Gornyi, Alexander D. Mirlin, Dmitry G. Polyakov. 2021-04-21. Generalized quantum measurements with matrix product states: Entanglement phase transition and clusterization. https://doi.org/10.1103/physrevresearch.4.023146

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