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arXiv · 2412.14285

Digital-Analog Simulations of Schr\"odinger Cat States in the Dicke-Ising Model

Dmitriy S. Shapiro·Yannik Weber·Tim Bode·Frank K. Wilhelm·Dmitry Bagrets
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Abstract

The Dicke-Ising model, one of the few paradigmatic models of matter-light interaction, exhibits a superradiant quantum phase transition above a critical coupling strength. However, in natural optical systems, its experimental validation is hindered by a "no-go theorem''. Here, we propose a digital-analog quantum simulator for this model based on an ensemble of interacting qubits coupled to a single-mode photonic resonator. We analyze the system's free energy landscape using field-theoretical methods and develop a digital-analog quantum algorithm that disentangles qubit and photon degrees of freedom through a parity-measurement protocol. This disentangling enables the emulation of a photonic Schr\"odinger cat state, which is a hallmark of the superradiant ground state in finite-size systems and can be unambiguously probed through the Wigner tomography of the resonator's field.

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Dmitriy S. Shapiro, Yannik Weber, Tim Bode, Frank K. Wilhelm, Dmitry Bagrets. 2024-12-18. Digital-Analog Simulations of Schr\"odinger Cat States in the Dicke-Ising Model. https://doi.org/10.1103/wbp6-y3vd

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