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Theory of control of spin/photon interface for quantum networks

Wang Yao·Ren-Bao Liu·L. J. Sham
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Abstract

A cavity coupling a charged nanodot and a fiber can act as a quantum interface, through which a stationary spin qubit and a flying photon qubit can be inter-converted via cavity-assisted Raman process. This Raman process can be controlled to generate or annihilate an arbitrarily shaped single-photon wavepacket by pulse-shaping the controlling laser field. This quantum interface forms the basis for many essential functions of a quantum network, including sending, receiving, transferring, swapping, and entangling qubits at distributed quantum nodes as well as a deterministic source and an efficient detector of a single photon wavepacket with arbitrarily specified shape and average photon number. Numerical study of noise effects on the operations shows high fidelity.

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Wang Yao, Ren-Bao Liu, L. J. Sham. 2004-07-07. Theory of control of spin/photon interface for quantum networks. https://doi.org/10.1103/physrevlett.95.030504

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