Long-Distance Superexchange between Semiconductor Quantum-Dot Electron Spins
Long-Distance Superexchange between Semiconductor Quantum-Dot Electron Spins
复制标题
半导体量子点电子自旋之间的长距离超级交换
DOI：
10.1103/physrevlett.126.017701
复制
发表时间：
2021
影响因子：
8.6
通讯作者：
Nichol, John M.
中科院分区：
文献类型：
--
作者：
Qiao, Haifeng;Kandel, Yadav P.;Fallahi, Saeed;Gardner, Geoffrey C.;Manfra, Michael J.;Hu, Xuedong;Nichol, John M.
半导体量子点自旋量子比特由于其长的相干时间和潜在的可扩展性，在量子信息处理方面具有很大的前景。然而，保持量子点自旋量子位之间的高连接性，这有利于具有最近邻耦合的线性阵列，对大规模量子计算提出了挑战。在这项工作中，我们提出的证据，长距离自旋链介导的超交换耦合的电子自旋量子比特在半导体量子点。我们弱耦合两个电子自旋的两端的两个网站的自旋链。根据链的自旋状态，我们观察到远端自旋之间的振荡。我们解决了两端的自旋和链本身的动力学，我们的测量与模拟一致。超交换是一种很有前途的在量子点自旋量子比特之间产生长距离耦合的技术。
Because of their long coherence times and potential for scalability, semiconductor quantum-dot spin qubits hold great promise for quantum information processing. However, maintaining high connectivity between quantum-dot spin qubits, which favor linear arrays with nearest neighbor coupling, presents a challenge for large-scale quantum computing. In this work, we present evidence for long-distance spin-chain-mediated superexchange coupling between electron spin qubits in semiconductor quantum dots. We weakly couple two electron spins to the ends of a two-site spin chain. Depending on the spin state of the chain, we observe oscillations between the distant end spins. We resolve the dynamics of both the end spins and the chain itself, and our measurements agree with simulations. Superexchange is a promising technique to create long-distance coupling between quantum-dot spin qubits.