Roos Christian F, Riebe Mark, Häffner Hartmut, Hänsel Wolfgang, Benhelm Jan, Lancaster Gavin P T, Becher Christoph, Schmidt-Kaler Ferdinand, Blatt Rainer
Institut für Experimentalphysik, Universität Innsbruck, Technikerstrasse 25, A-6020 Innsbruck, Austria.
Science. 2004 Jun 4;304(5676):1478-80. doi: 10.1126/science.1097522.
We report the deterministic creation of maximally entangled three-qubit states-specifically the Greenberger-Horne-Zeilinger (GHZ) state and the W state-with a trapped-ion quantum computer. We read out one of the qubits selectively and show how GHZ and W states are affected by this local measurement. Additionally, we demonstrate conditional operations controlled by the results from reading out one qubit. Tripartite entanglement is deterministically transformed into bipartite entanglement by local operations only. These operations are the measurement of one qubit of a GHZ state in a rotated basis and, conditioned on this measurement result, the application of single-qubit rotations.
我们报告了利用囚禁离子量子计算机确定性地制备最大纠缠三量子比特态,具体而言是格林伯格-霍恩-泽林格(GHZ)态和W态。我们选择性地读出其中一个量子比特,并展示了GHZ态和W态是如何受到这种局部测量影响的。此外,我们演示了由读出一个量子比特的结果控制的条件操作。仅通过局部操作就可以将三方纠缠确定性地转化为两方纠缠。这些操作包括在一个旋转基下对GHZ态的一个量子比特进行测量,并基于此测量结果应用单量子比特旋转。