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Register a new userFault-Tolerant Multi-Qubit Geometric Entangling Gates Using Photonic Cat Qubits
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We propose a protocol to implement multi-qubit geometric gates (i.e., the M{o}lmer-S{o}rensen gate) using photonic cat qubits. These cat qubits stored in high-$Q$ resonators are promising for hardware-efficient universal quantum computing. Specifically, in the limit of strong two-photon drivings, phase-flip errors of the cat qubits are effectively suppressed, leaving only a bit-flip error to be corrected. A geometric evolution guarantees the robustness of the protocol against stochastic noise along the evolution path. Moreover, by changing detunings of the cavity-cavity couplings at a proper time, the protocol can be robust against control imperfections (e.g., the total evolution time) without introducing extra noises into the system. As a result, the gate can produce multi-mode entangled cat states in a short time with high fidelities.
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