Fakultät für Physik, Ludwig-Maximilians-Universität, München, Germany.
Phys Rev Lett. 2010 Dec 31;105(26):265303. doi: 10.1103/PhysRevLett.105.265303. Epub 2010 Dec 29.
We report on the controlled creation of a valence bond state of delocalized effective-spin singlet and triplet dimers by means of a bichromatic optical superlattice. We demonstrate a coherent coupling between the singlet and triplet states and show how the superlattice can be employed to measure the singlet-fraction employing a spin-blockade effect. Our method provides a reliable way to detect and control nearest-neighbor spin correlations in many-body systems of ultracold atoms. Being able to measure these correlations is an important ingredient in studying quantum magnetism in optical lattices. We furthermore employ a SWAP operation between atoms which are part of different triplets, thus effectively increasing their bond-length. Such a SWAP operation provides an important step towards the massively parallel creation of a multiparticle entangled state in the lattice.
我们报告了通过双频光学超晶格来控制离域有效单重态和三重态二聚体的价键态的产生。我们演示了单态和三重态之间的相干耦合，并展示了如何利用超晶格中的自旋阻塞效应来测量单态分数。我们的方法为探测和控制超冷原子多体系统中的最近邻自旋关联提供了一种可靠的手段。能够测量这些关联是研究光学晶格中的量子磁学的一个重要组成部分。我们还利用不同三重态的原子之间的 SWAP 操作，从而有效地增加了它们的键长。这种 SWAP 操作为在晶格中大规模并行地创建多粒子纠缠态提供了重要的一步。
