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arXiv:2608.19310

Dissipation-enhanced scrambling in the SYK model coupled to a lossy cavity

Pietro Pelliconi, Bastien Lapierre, Shinsei Ryu

quant-phcond-mat.str-elhep-thSubmitted Aug 19, 2026• Announced Aug 21, 2026• 0 citations
v1 · Aug 19, 2026v2 · Aug 24, 2026
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Abstract

We study the Yukawa-Sachdev-Ye-Kitaev model, a disordered model of $N$ Majorana fermions and $R=γN$ bosons in which the bosons are linearly coupled to independent realizations of SYK $p$-body interactions, in the presence of dissipation, modeled by a Lindblad master equation. Motivated by recent proposals for implementing SYK models in quantum simulators, we focus on bosonic leakage at rate $κ$. Initializing the system in the steady state, we analyze the late-time fermionic relaxation rate and the Lyapunov exponent, solving the large-$N$ theory both numerically and for $p$ large, finding a rich landscape of dynamical behaviors. Most notably, the Lyapunov exponent remains positive for every value of $κ$ and, for $p>2$, can even grow as $κ$ increases. The QED case $p=2$, which lies between the fully chaotic regime $p>2$ and the integrable case $p=1$, exhibits special features. We also identify a critical value of the boson-to-fermion ratio $γ_c \approx 2/p^2$ separating distinct dynamical regimes.

Comments
15 pages, 3 figures

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