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arXiv · 2105.08371

Parity-symmetry-breaking quantum phase transition via parametric drive in a cavity magnonic system

Guo-Qiang Zhang·Zhen Chen·Wei Xiong·Chi-Hang Lam·J. Q. You
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Abstract

We study the parity-symmetry-breaking quantum phase transition (QPT) in a cavity magnonic system driven by a parametric field, where the magnons in a ferrimagnetic yttrium-iron-garnet sphere strongly couple to a microwave cavity. With appropriate parameters, this cavity magnonic system can exhibit a rich phase diagram, including the parity-symmetric phase, parity-symmetry-broken phase, and bistable phase. When increasing the drive strength beyond a critical threshold, the cavity magnonic system undergoes either a first- or second-order nonequilibrium QPT from the parity-symmetric phase with microscopic excitations to the parity-symmetry-broken phase with macroscopic excitations, depending on the parameters of the system. Our work provides an alternate way to engineer the QPT in a hybrid quantum system containing the spin ensemble in a ferri- or ferromagnetic material with strong exchange interactions.

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Guo-Qiang Zhang, Zhen Chen, Wei Xiong, Chi-Hang Lam, J. Q. You. 2021-05-18. Parity-symmetry-breaking quantum phase transition via parametric drive in a cavity magnonic system. https://doi.org/10.1103/physrevb.104.064423

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