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arXiv · 2206.09540

Chiral current in Floquet cavity-magnonics

Shi-fan Qi·Jun Jing
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Abstract

Floquet engineering can induce complex collective behaviour and interesting synthetic gauge-field in quantum systems through temporal modulation of system parameters by periodic drives. Using a Floquet drive on frequencies of the magnon modes, we realize a chiral state-transfer in a cavity-magnonic system. The time-reversal symmetry is broken in such a promising platform for coherent information processing. In particular, the photon mode is adiabatically eliminated in the large-detuning regime and the magnon modes under conditional longitudinal drives can be indirectly coupled to each other with a phase-modulated interaction. The effective Hamiltonian is then used to generate chiral currents in a circular loop, whose dynamics is evaluated to measure the symmetry of the system Hamiltonian. Beyond the dynamics limited in the manifold with a fixed number of excitations, our protocol applies to the continuous-variable systems with arbitrary states. Also it is found to be robust against the systematic errors in the photon-magnon coupling strength and Kerr nonlinearity.

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Shi-fan Qi, Jun Jing. 2022-10-11. Chiral current in Floquet cavity-magnonics. https://doi.org/10.1103/physreva.106.033711

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