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arXiv · 2211.15592

Cascaded dynamics of a periodically driven dissipative dipolar system

Saptarshi Saha·Rangeet Bhattacharyya
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Abstract

Recent experiments show that periodic drives on dipolar systems lead to long-lived prethermal states. These systems are weakly coupled to the environment and reach prethermal states in a timescale much shorter than the timescale for thermalization. Such nearly-closed systems have previously been analyzed using Floquet formalism, which shows the emergence of a prethermal plateau. We use a fluctuation-regulated quantum master equation (FRQME) to describe these systems. In addition to the system-environment coupling, FRQME successfully captures the dissipative effect from the various local interactions in the system. Our investigation reveals a cascaded journey of the system to a final steady state. The cascade involves a set of prethermal or arrested states characterized by a set of quasi-conserved quantities. We show that these prethermal states emerge in a timescale much shorter than the relaxation timescale. We also find and report the existence of a critical limit beyond which the prethermal plateau ceases to exist.

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Saptarshi Saha, Rangeet Bhattacharyya. 2022-11-28. Cascaded dynamics of a periodically driven dissipative dipolar system. https://doi.org/10.1103/physreva.107.022206

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