论文标题
具有辅助空间的低成本弗雷德金门
Low-cost Fredkin gate with auxiliary space
论文作者
论文摘要
有效的量子信息处理部分是最小化量子逻辑门所需的量子资源。在这里，我们通过利用辅助Hilbert空间来优化，最大2N+1个二克门和2N单Qudit门的N对照Qubit Fredkin门具有最大2n+1个两倍的门。对于模拟任意N Qubit Fredkin门的早期结果所需的逻辑门数量。特别是，一个控制的Qubit Fredkin门（需要三个Qutrit-quit Quitt偏s-swap门）的最佳结果破坏了五个两分Qubit Gates的理论非构造性下限。此外，使用其他空间模式的自由度，我们设计了一种可能的架构来实现具有线性光学元件的极化编码的弗雷德金门。
Effective quantum information processing is tantamount in part to the minimization the quantum resources needed by quantum logic gates. Here, we propose an optimization of an n-controlled-qubit Fredkin gate with a maximum of 2n+1 two-qubit gates and 2n single-qudit gates by exploiting auxiliary Hilbert spaces. The number of logic gates required improves on earlier results on simulating arbitrary n-qubit Fredkin gates. In particular, the optimal result for one-controlled-qubit Fredkin gate (which requires three qutrit-qubit partial-swap gates) breaks the theoretical nonconstructive lower bound of five two-qubit gates. Furthermore, using an additional spatial-mode degree of freedom, we design a possible architecture to implement a polarization-encoded Fredkin gate with linear optical elements.
