Precise Control of Entanglement in Multinuclear Spin Registers Coupled to Defects
Precise Control of Entanglement in Multinuclear Spin Registers Coupled to Defects
复制标题
DOI：
10.1103/physrevx.13.011004
复制
发表时间：
2022-03
影响因子：
12.5
通讯作者：
E. Takou;Edwin Barnes;S. Economou
中科院分区：
文献类型：
--
作者：
E. Takou;Edwin Barnes;S. Economou
量子网络在量子信息任务中发挥着不可或缺的作用，例如安全通信，增强量子传感和分布式计算。最成熟和最有前途的量子网络平台是金刚石中的氮空位中心和固体中的其他色心。使用这些系统用于网络应用的挑战之一是可控地操纵电子和核自旋寄存器之间的纠缠，尽管超精细相互作用的始终开启的性质，这使得这是一个固有的多体量子系统。在这里，我们开发了一个一般的形式主义，量化和控制纠缠的产生在一个任意大的核自旋寄存器耦合到色心电子自旋。我们提供了一个可靠的测量核自旋选择性，通过准确地纳入我们的治疗与不需要的核的动力学。我们还展示了如何通过使用动态解耦序列来实现直接多体门，与基于单个核自旋的顺序纠缠的协议相比，大大减少了总门时间。我们量化的性能，这样的门操作中存在不必要的残余纠缠链接，捕捉整个核自旋寄存器的动态。最后，利用一个27核自旋寄存器的实验参数，我们展示了如何制备用于量子纠错的高保真纠缠态。
Quantum networks play an indispensable role in quantum information tasks such as secure communications, enhanced quantum sensing, and distributed computing. Among the most mature and promising platforms for quantum networking are nitrogen-vacancy centers in diamond and other color centers in solids. One of the challenges in using these systems for networking applications is to controllably manipulate entanglement between the electron and the nuclear spin register despite the always-on nature of the hyperfine interactions, which makes this an inherently many-body quantum system. Here, we develop a general formalism to quantify and control the generation of entanglement in an arbitrarily large nuclear spin register coupled to a color center electronic spin. We provide a reliable measure of nuclear spin selectivity, by exactly incorporating into our treatment the dynamics with unwanted nuclei. We also show how to realize direct multipartite gates through the use of dynamical decoupling sequences, drastically reducing the total gate time compared to protocols based on sequential entanglement with individual nuclear spins. We quantify the performance of such gate operations in the presence of unwanted residual entanglement links, capturing the dynamics of the entire nuclear spin register. Finally, using experimental parameters of a well-characterized 27 nuclear spin register device, we show how to prepare with high fidelity entangled states for quantum error correction.