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arXiv · 2609.34201

Quantum memory in an effective $Λ$-type system using dynamic detuning control of a superconducting qubit pair

Hsin Chang·Kai-I Chu·Ite A. Yu·Yen-Hsiang Lin·Yung-Fu Chen
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Abstract

We theoretically investigate quantum-light storage in an effective $Λ$-type system formed by a pair of tunable superconducting qubits coupled to a semi-infinite transmission line and separated by half a wavelength. The frequency detuning between the qubits directly couples the superradiant excited state and the subradiant metastable state. By adjusting the qubit detuning, the system exhibits a controllable spectral response accompanied by slow-light behavior. Dynamically controlling the detuning enables an incident quantum field to be mapped onto the subradiant collective state, stored as a long-lived excitation, and subsequently retrieved on demand. Our results establish the proposed system as a minimal and tunable quantum-memory architecture for scalable superconducting quantum networks.

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Hsin Chang, Kai-I Chu, Ite A. Yu, Yen-Hsiang Lin, Yung-Fu Chen. 2026-09-28. Quantum memory in an effective $Λ$-type system using dynamic detuning control of a superconducting qubit pair. https://arxiv.org/abs/2609.34201

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