Wigner-Negative Magnon Steady States from Incoherent Qubit Pumping

Yan Liu; Jiahua Li

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arXiv · 2606.22753

Wigner-Negative Magnon Steady States from Incoherent Qubit Pumping

Yan Liu·Jiahua Li

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Abstract

We show that incoherently pumped qubits can realize a cascaded dissipative mechanism for stabilizing Wigner-negative magnon steady states. The mechanism combines qubit pumping with dispersive magnon-number selectivity to direct the steady-state population toward selected magnon Fock states. In the single-qubit case, the single-magnon population can approach unity, accompanied by strong antibunching and pronounced Wigner negativity. Extending the same principle to multiple qubits yields Wigner-negative steady states dominated by higher magnon Fock components. We further derive an analytical birth--death model that captures the mechanism and agrees with numerical results. These results establish incoherent qubit pumping as a controllable dissipative resource for generating nonclassical magnon states in hybrid quantum systems.

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Yan Liu, Jiahua Li. 2026-06-22. Wigner-Negative Magnon Steady States from Incoherent Qubit Pumping. https://arxiv.org/abs/2606.22753

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