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Quantum computation with coupled-quantum-dots embedded in optical microcavities

Xin-Qi Li·YiJing Yan
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Abstract

Based on an idea that spatial separation of charge states can enhance quantum coherence, we propose a scheme for quantum computation with quantum bit (qubit) constructed from two coupled quantum dots. Quantum information is stored in electron-hole pair state with the electron and hole locating in different dots, which enables the qubit state being very long-lived. Universal quantum gates involving any pair of qubits are realized by coupling the quantum dots through cavity photon which is a hopeful candidate to transfer long-range information. Operation analysis is carried out by estimating the gate time versus the decoherence time.

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Xin-Qi Li, YiJing Yan. 2002-03-29. Quantum computation with coupled-quantum-dots embedded in optical microcavities. https://doi.org/10.1103/physrevb.65.205301

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