All-optical measurement-based quantum-information processing in quantum dots.
All-optical measurement-based quantum-information processing in quantum dots.
复制标题
量子点中基于全光学测量的量子信息处理。
DOI：
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发表时间：
2006
影响因子：
8.6
通讯作者：
T. Stace
中科院分区：
文献类型：
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作者：
A. Kolli;B. Lovett;S. Benjamin;T. Stace
量子比特上的奇偶性测量可以产生可扩展量子计算所必需的纠缠资源。在这里，我们描述了一种方法，用于快速光学宇称测量耦合量子点内的电子自旋量子比特。的测量方案，这可以实现与现有技术，包括激子状态的光激发，然后监测弛豫。在观测到光子的条件下，系统被投影到奇/偶宇称子空间中。我们的模型结合了所有主要的误差来源，包括检测器效率低下，空间分离和非共振的点的影响，以及不必要的激励。通过分析处理，我们建立了该计划是强大的，这样的影响。两个应用程序：实现一个受控的非门，和一种技术，用于增长大规模的图形状态。
Parity measurements on qubits can generate the entanglement resource necessary for scalable quantum computation. Here we describe a method for fast optical parity measurements on electron spin qubits within coupled quantum dots. The measurement scheme, which can be realized with existing technology, consists of the optical excitation of excitonic states followed by monitored relaxation. Conditional on the observation of a photon, the system is projected into the odd/even-parity subspaces. Our model incorporates all the primary sources of error, including detector inefficiency, effects of spatial separation and nonresonance of the dots, and also unwanted excitations. Through an analytical treatment we establish that the scheme is robust to such effects. Two applications are presented: a realization of a controlled-NOT gate, and a technique for growing large scale graph states.