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arXiv · 2107.14647

Finite-size scalings in measurement-induced dynamical phase transition

Ranjan Modak·Debraj Rakshit·Ujjwal Sen
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Abstract

Repetitive measurements can cause freezing of dynamics of a quantum state, which is known as quantum Zeno effect. We consider an interacting one-dimensional fermionic system and study the fate of the many-body quantum Zeno transition if the system is allowed to evolve repetitively under the unitary dynamics, followed by a measurement process. Measurement induced phase transitions can be accessed by tuning a suitably defined parameter representing measurement strength (frequency). We use different diagnostics, such as long-time evolved entanglement entropy, purity and their fluctuations in order to characterize the transition. We further perform a finite size scaling analysis in order to detect the transition points and evaluate associated scaling exponents via an unbiased numerical strategy of cost function minimization, which provides a platform to compare finite-size scaling ansatze proposed previously in context of many-body Zeno transition.

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Ranjan Modak, Debraj Rakshit, Ujjwal Sen. 2021-07-30. Finite-size scalings in measurement-induced dynamical phase transition. https://arxiv.org/abs/2107.14647

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