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arXiv · 2610.23573

Action-Quantized Scar Multiplets and Dissipative Cat States from Fractal Period-Locking in the Open Quantum Baker Map

Leonardo Ermann
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Abstract

We open the quantum baker map with a position window of width $w$ and center $q_c$. Classical pruning tiles the $(q_c,w)$ plane into diamonds where the $T$ leading resonances form root-of-unity multiplets. At $w=1/2$ one periodic orbit survives for almost every $q_c$, and the multiplets are quantized without free parameters: their modulus $2^{-1/2}$ saturates the pressure bound and their phase is the orbit action. They form cycling multicomponent cat states, and the opening becomes one mid-circuit measurement, enabling spectroscopy with $\sim10^2$ shots on quantum processors.

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Leonardo Ermann. 2026-10-16. Action-Quantized Scar Multiplets and Dissipative Cat States from Fractal Period-Locking in the Open Quantum Baker Map. https://arxiv.org/abs/2610.23573

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