论文标题
在不均匀磁场下介导的superexchange的标志转换
Sign-switching of superexchange mediated by few electrons under non-uniform magnetic field
论文作者
论文摘要
远处旋转之间的远距离相互作用是实现大量子点网络的重要组成部分，在该网络中，可以选择性地解决两对旋转之间的耦合。关于中间电子状态促进的远程旋转之间相干逻辑状态振荡的最新实验铺平了大规模量子信息处理的第一步。达到这个最终目标需要对不同量子点空间布置和电子构型的超级交流相互作用进行广泛研究。在这里，我们考虑了一个线性三重量子点，在外点中有两个反平行的旋转，形成逻辑状态，而中间点中的各种电子形成介体，从而促进了甲壳上的相互作用。我们表明，当介导的电子数量增加时，甲基次数会增强。此外，我们表明在调解器点中形成四电子三重态进一步增强了甲基化强度。我们的工作可以是通过可控且密集的连接性扩展量子点阵列的指南。
Long range interaction between distant spins is an important building block for the realization of large quantum-dot network in which couplings between pairs of spins can be selectively addressed. Recent experiments on coherent logical states oscillation between remote spins facilitated by intermediate electron states has paved the first step for large scale quantum information processing. Reaching this ultimate goal requires extensive studies on the superexchange interaction on different quantum-dot spatial arrangements and electron configurations. Here, we consider a linear triple-quantum-dot with two anti-parallel spins in the outer dots forming the logical states while various number of electrons in the middle dot forming a mediator, which facilitates the superexchange interaction. We show that the superexchange is enhanced when the number of mediating electrons increases. In addition, we show that forming a four-electron triplet in the mediator dot further enhance the superexchange strength. Our work can be a guide to scale up the quantum-dot array with controllable and dense connectivity.
