LNE-SYRTE, Observatoire de Paris, LNE, CNRS, UPMC, 61 avenue de l'Observatoire, 75014 Paris, France.
Phys Rev Lett. 2011 May 27;106(21):213002. doi: 10.1103/PhysRevLett.106.213002.
Raman laser pulses are used to induce coherent tunneling between neighboring sites of a vertical 1D optical lattice. Such tunneling occurs when the detuning of a probe laser from the atomic transition frequency matches multiples of the Bloch frequency, allowing for a spectroscopic control of the coupling between Wannier-Stark (WS) states. In particular, we prepare coherent superpositions of WS states of adjacent sites, and investigate the coherence time of these superpositions by realizing a spatial interferometer. This scheme provides a powerful tool for coherent manipulation of external degrees of freedom of cold atoms, which is a key issue for quantum information processing.
拉曼激光脉冲被用来诱导垂直一维光学晶格中相邻位点之间的相干隧穿。当探测激光从原子跃迁频率的失谐量与布洛克频率的倍数匹配时，就会发生这种隧穿，从而可以对沃纳-斯塔克（Wannier-Stark，WS）态之间的耦合进行光谱控制。具体来说，我们通过实现空间干涉仪来制备相邻位点的 WS 态相干叠加，并通过实现空间干涉仪来研究这些叠加的相干时间。该方案为相干操控冷原子的外部自由度提供了一种强大的工具，这是量子信息处理的关键问题。
