论文标题
通过脉冲控制几乎精确的旋转链中的状态转移
Almost exact state transfer in a spin chain via pulse control
论文作者
论文摘要
通过旋转链的量子通信已得到广泛研究。在这种情况下，通过线性排列的旋转通过均匀的最近邻邻耦合连接的状态转移可以作为自然选择，并具有最小的控制要求。但是，由于链的分散，量子状态通常不能通过均匀耦合链完美传递。在这里，我们提出了一种有效的量子控制技术，以实现量子自旋链中几乎确切的状态转移（AEST）。该策略是在进化中添加泄漏消除操作员（LEO）哈密顿量，该脉冲控制作用于完美状态传输子空间。通过使用单组分Feshbach PQ分区技术，我们可以在所需的脉冲上获得条件。然后可以在合适的脉冲强度和持续时间下通过自旋链进行aest。
Quantum communication through spin chains has been extensively investigated. In this scenario, state transfer through linearly arranged spins connected by uniform nearest-neighbor couplings qualifies as a natural choice, with minimal control requirements. However, quantum states usually cannot be perfectly transferred through a uniformly coupled chain due to the dispersion of the chain. Here, we propose an effective quantum control technique to realize almost exact state transfer (AEST) in a quantum spin chain. The strategy is to add a leakage elimination operator (LEO) Hamiltonian to the evolution, which implements a sequence of pulse control acting on a perfect state transfer subspace. By using the one-component Feshbach PQ partitioning technique, we obtain the conditions over the required pulses. AEST through a spin chain can then be obtained under a suitable pulse intensity and duration.
