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Effect of exchange interaction on fidelity of quantum state transfer from a photon qubit to an electron-spin qubit

Yoshiaki Rikitake·Hiroshi Imamura
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Abstract

We analyzed the fidelity of the quantum state transfer (QST) from a photon-polarization qubit to an electron-spin-polarization qubit in a semiconductor quantum dot, with special attention to the exchange interaction between the electron and the simultaneously created hole. In order to realize a high-fidelity QST we had to separate the electron and hole as soon as possible, since the electron-hole exchange interaction modifies the orientation of the electron spin. Thus, we propose a double-dot structure to separate the electron and hole quickly, and show that the fidelity of the QST can reach as high as 0.996 if the resonant tunneling condition is satisfied.

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Yoshiaki Rikitake, Hiroshi Imamura. 2006-08-24. Effect of exchange interaction on fidelity of quantum state transfer from a photon qubit to an electron-spin qubit. https://doi.org/10.1103/physrevb.74.081307

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