论文标题
具有多个单个光子自由度的量子控制的量子门的实验证明
Experimental Demonstration of a Quantum Controlled-SWAP Gate with Multiple Degrees of Freedom of a Single Photon
论文作者
论文摘要
优化量子门的物理实现对于构建量子计算机很重要。受控的Swap门（也称为Fredkin Gate）可以广泛适用于各种量子信息处理方案。在本研究中，我们在单光子杂种系统中提出并实现了实现量子弗雷德金门。极化用作控制量子，并在由光子轨道角动量跨越的四维希尔伯特空间中实现掉期操作。在我们的实验中，量子弗雷德金门的有效转换率$ \ MATHCAL {P} $为$（95.4 \ pm 2.6）\％$。此外，我们发现可以通过使用我们的量子弗雷德金门来制备一种格林伯格 - 居民 - 齐伊林格状态，这些非散发状态可以通过违反Mermin不平等的量子表现出其量子上下文特征。我们的实验设计和编码方法可用于高维和混合编码量子系统中的量子计算和量子基础研究。
Optimizing the physical realization of quantum gates is important to build a quantum computer. The controlled-SWAP gate, also named Fredkin gate, can be widely applicable in various quantum information processing schemes. In the present research, we propose and experimentally implement quantum Fredkin gate in a single-photon hybrid-degrees-of-freedom system. Polarization is used as the control qubit, and SWAP operation is achieved in a four-dimensional Hilbert space spanned by photonic orbital angular momentum. The effective conversion rate $\mathcal{P}$ of the quantum Fredkin gate in our experiment is $(95.4\pm 2.6)\%$. Besides, we find that a kind of Greenberger-Horne-Zeilinger-like states can be prepared by using our quantum Fredkin gate, and these nonseparale states can show its quantum contextual characteristic by the violation of Mermin inequality. Our experimental design and coding method are useful for quantum computing and quantum fundamental study in high-dimensional and hybrid coding quantum systems.
