Department Physik, Naturwissenschaftlich-Technische Fakultät, Universität Siegen, 57068 Siegen, Germany.
Department of Physics, Sofia University, 5 James Bourchier Boulevard, 1164 Sofia, Bulgaria.
Sci Adv. 2016 Jul 8;2(7):e1600093. doi: 10.1126/sciadv.1600093. eCollection 2016 Jul.
Using trapped atomic ions, we demonstrate a tailored and versatile effective spin system suitable for quantum simulations and universal quantum computation. By simply applying microwave pulses, selected spins can be decoupled from the remaining system and, thus, can serve as a quantum memory, while simultaneously, other coupled spins perform conditional quantum dynamics. Also, microwave pulses can change the sign of spin-spin couplings, as well as their effective strength, even during the course of a quantum algorithm. Taking advantage of the simultaneous long-range coupling between three spins, a coherent quantum Fourier transform-an essential building block for many quantum algorithms-is efficiently realized. This approach, which is based on microwave-driven trapped ions and is complementary to laser-based methods, opens a new route to overcoming technical and physical challenges in the quest for a quantum simulator and a quantum computer.
我们利用被困的原子离子，展示了一个经过精心设计且功能多样的有效自旋系统，该系统适用于量子模拟和通用量子计算。通过简单地施加微波脉冲，可以将选定的自旋与剩余系统解耦，从而充当量子存储器，同时，其他耦合自旋会执行条件量子动力学。此外，微波脉冲甚至可以在量子算法的过程中改变自旋-自旋耦合的符号以及其有效强度。利用三个自旋之间的同时远程耦合，高效地实现了相干量子傅里叶变换——这是许多量子算法的基本构建块。这种基于微波驱动的被困离子的方法，与基于激光的方法互补，为克服量子模拟器和量子计算机研究中的技术和物理挑战开辟了新途径。
