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arXiv · 2304.05886

Third-order exceptional point in an ion-cavity system

Jinuk Kim·Taegyu Ha·Donggeon Kim·Dowon Lee·Ki-Se Lee·Jongcheol Won·Youngil Moon·Moonjoo Lee
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Abstract

We investigate a scheme for observing the third-order exceptional point (EP3) in an ion-cavity setting. In the lambda-type level configuration, the ion is driven by a pump field, and the resonator is probed with another weak laser field. We exploit the highly asymmetric branching ratio of an ion's excited state to satisfy the weak-excitation limit, which allows us to construct the non-Hermitian Hamiltonian $(H_{\textrm{nH}})$. Via fitting the cavity-transmission spectrum, the eigenvalues of $H_{\textrm{nH}}$ are obtained. The EP3 appears at a point where the Rabi frequency of the pump laser and the atom-cavity coupling constant balance the loss rates of the system. Feasible experimental parameters are provided.

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Jinuk Kim, Taegyu Ha, Donggeon Kim, Dowon Lee, Ki-Se Lee, Jongcheol Won, Youngil Moon, Moonjoo Lee. 2023-04-12. Third-order exceptional point in an ion-cavity system. https://doi.org/10.1063/5.0168372

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