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arXiv · 2609.28492

The non-equilibrium condensate-like state in multi-mode driven dissipative superconducting quantum circuit

Jing Li·Chaoying Zhao
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Abstract

The effective decay rate of traditional single mode model for an open quantum system can't accurately described the exchange between intermodes and dissipation caused by the environment,therefore we can not clearly see the occupation pathway of target mode or the transient participation of auxiliary modes.At the same time,we also can't address the selective dissipation pathways resulting from the circuit design.In order to solving above problem,we adopt fluxonium-transmon-transmon (FTT)-based three mode model to describe dynamical characteristics of dissipation spectrum in superconducting quantum circuits.In terms of periodic flux modulation,we find out the pathways of intermode occupation transfer and environmental release for the target fluxonium changes from a high occupation nonequilibrium condensate-like state to low occupation equilibrium Bose-Einstein condensation(BEC)state.Without increasing the intrinsic loss of the target mode in the process of adjusting the auxiliary mode,we furthermore obtain additional selectively engaged environmental dissipative pathway.Our model can provides a new design perspective for non-equilibrium state recovery in a controllable dissipation superconducting quantum circuit.

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Jing Li, Chaoying Zhao. 2026-09-01. The non-equilibrium condensate-like state in multi-mode driven dissipative superconducting quantum circuit. https://arxiv.org/abs/2609.28492

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