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arXiv · 2603.13125

Universal monitored dynamics in multimode bosonic systems

Shivam Patel·Catherine McCarthy·Ahana Chakraborty·Jordan Huang·Thomas J. DiNapoli·Romain Vasseur·J. H. Pixley·Srivatsan Chakram
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Abstract

We propose a route to study monitored many-body dynamics in multimode bosonic systems using circuit quantum electrodynamics. In this experimental setting, we construct several bosonic models comprising brickwork circuits built from beam-splitter gates, local parity measurements, and optional on-site Hubbard interactions, and diagnose their monitored dynamics via ancilla purification and a learnability-based probe. Under parity measurements, generic gate sets exhibit behavior that is largely consistent with a conventional measurement-induced phase transition, while a special class of beam-splitter circuits shows an apparent critical-like high-measurement regime in which purification times scale linearly with system size. We show that for realistic noise, gate, and measurement rates, these signatures are observable with near-term circuit QED hardware.

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Shivam Patel, Catherine McCarthy, Ahana Chakraborty, Jordan Huang, Thomas J. DiNapoli, Romain Vasseur, J. H. Pixley, Srivatsan Chakram. 2026-03-13. Universal monitored dynamics in multimode bosonic systems. https://arxiv.org/abs/2603.13125

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