arXiv:quant-ph/0407060 · Physical Review Letters

Theory of Control of the Spin-Photon Interface for Quantum Networks

Wang Yao, Ren‐Bao Liu, Lu Jeu Sham

Published Jul 13, 2005• 208 citations

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 interconverted via a cavity-assisted Raman process. This Raman process can be made to generate or annihilate an arbitrarily shaped single-photon wave packet 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 wave packet with arbitrarily specified shape and average photon number. Numerical study of errors from noise and system parameters on the operations shows high fidelity and robust tolerance.

DOI: 10.1103/physrevlett.95.030504

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