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arXiv · 2310.08388

Is the photon-blockade breakdown a quantum effect? A neoclassical story

Árpád Kurkó·Nikolett Német·András Vukics
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Abstract

The photon-blockade breakdown bistability can be intuitively explained invoking the energy spectrum of the interacting qubit-mode system. Yet, the neoclassical solution of the driven-dissipative Jaynes-Cummings model has been shown to capture several key aspects of the phenomenon. In this paper, we set out to compare a fully quantum solution with the neo- and semi-classical solutions. Although the neoclassical theory is founded on the assumption of a pure partial state for the qubit, it is not simply the $\gamma \to 0$ limit of the semiclassical theory; the semi- vs. neo-classical duality being a case of non-commutativity of limits. Furthermore, we show that the neoclassical predictions still hold in case of a small qubit decay. Tracing the bistable behavior for different detunings, we show that it is robust over a significant range of $\Delta$ values. We demonstrate that the aptitude of the neoclassical description is founded on the high quantum purity of the bright state of the photon-blockade breakdown bistability, which sharply differentiates this phenomenology from conventional optical bistability. It is thereby demonstrated that driven-dissipative dynamics can produce closely separable pure steady states in an interacting bipartite.

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Árpád Kurkó, Nikolett Német, András Vukics. 2023-10-12. Is the photon-blockade breakdown a quantum effect? A neoclassical story. https://doi.org/10.1364/josab.522547

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