Non-unitary Entanglement Dynamics in Continuous Variable Systems

• URL: http://arxiv.org/abs/2103.06507v2
• Date: Thu, 23 Dec 2021 23:06:29 GMT
• Title: Non-unitary Entanglement Dynamics in Continuous Variable Systems
• Abstract summary: We show that when the measurement rate is nonzero, the steady state entanglement entropy saturates to an area-law scaling. This is different from a many-body qubit system, where a generic entanglement transition is widely expected.
• Score: 6.723539428281127
• License: http://arxiv.org/licenses/nonexclusive-distrib/1.0/
• Abstract: We construct a random unitary Gaussian circuit for continuous-variable (CV) systems subject to Gaussian measurements. We show that when the measurement rate is nonzero, the steady state entanglement entropy saturates to an area-law scaling. This is different from a many-body qubit system, where a generic entanglement transition is widely expected. Due to the unbounded local Hilbert space, the time scale to destroy entanglement is always much shorter than the one to build it, while a balance could be achieved for a finite local Hilbert space. By the same reasoning, the absence of transition should also hold for other non-unitary Gaussian CV dynamics.

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