Zhou Hui, Chen Xi, Nie Xinfang, Bian Ji, Ji Yunlan, Li Zhaokai, Peng Xinhua
Department of Physics, Shaanxi University of Science and Technology, Xi'an 710021, China.
Hefei National Laboratory for Physical Sciences at the Microscale and Department of Modern Physics, University of Science and Technology of China, Hefei 230026, China; CAS Key Laboratory of Microscale Magnetic Resonance, University of Science and Technology of China, Hefei 230026, China.
Sci Bull (Beijing). 2019 Jul 15;64(13):888-895. doi: 10.1016/j.scib.2019.05.018. Epub 2019 May 25.
Quantum state transfer between two distant parties is at the heart of quantum computation and quantum communication. Among the various protocols, the counterdiabatic driving (CD) method, by suppressing the unwanted transitions with an auxiliary Hamiltonian H(t), offers a fast and robust strategy to transfer quantum states. However, H(t) term often takes a complicated form in higher-dimensional systems and is difficult to realize in experiment. Recently, the Floquet-engineered method was proposed to emulate the dynamics induced by H(t) without the need for complex interactions in multi-qubit systems, which can accelerate the adiabatic process through the fast-oscillating control in the original Hamiltonian H(t). Here, we apply this method in the Heisenberg spin chains, with only control of the two marginal couplings, to achieve the fast, high-fidelity, and robust quantum state transfer. Then we report an experimental implementation of our scheme using a nuclear magnetic resonance simulator. The experimental results demonstrate the feasibility of this method in complex many-body system and thus provide a new alternative to realize the high-fidelity quantum state manipulation in practice.
两个远距离量子比特之间的量子态转移是量子计算和量子通信的核心。在各种协议中，通过辅助哈密顿量H(t)抑制不需要的跃迁的反绝热驱动（CD）方法，为量子态转移提供了一种快速且稳健的策略。然而，在高维系统中，H(t)项通常具有复杂的形式，并且在实验中难以实现。最近，人们提出了弗洛凯工程方法，无需多量子比特系统中的复杂相互作用即可模拟由H(t)诱导的动力学，该方法可以通过原始哈密顿量H(t)中的快速振荡控制来加速绝热过程。在这里，我们将此方法应用于海森堡自旋链，仅控制两个边缘耦合，以实现快速、高保真且稳健的量子态转移。然后，我们报告了使用核磁共振模拟器对我们方案的实验实现。实验结果证明了该方法在复杂多体系统中的可行性，从而为在实际中实现高保真量子态操纵提供了一种新的选择。
