Ultracold quantum gases in triangular optical lattices
Ultracold quantum gases in triangular optical lattices
复制标题
DOI：
10.1088/1367-2630/12/6/065025
复制
发表时间：
2010-06-28
影响因子：
3.3
通讯作者：
Sengstock, K.
中科院分区：
文献类型：
--
作者：
Becker, C.;Soltan-Panahi, P.;Sengstock, K.
近年来，在光学晶格中的超冷原子领域的令人兴奋的发展导致了许多致力于量子模拟问题的理论建议，例如从凝聚态物理中已知的问题。许多这样的想法需要非立方晶格几何的实验环境。在本文中，我们报告了一种允许生成三角形和六边形光学晶格的通用三光束晶格的实现。作为重要的一步，我们首次在这种晶格几何中对超流体-莫特绝缘体（SF-MI）的量子相变进行了详细的观察和研究。除此之外，我们还研究了三角形光学晶格势存在下的自旋玻色-爱因斯坦凝聚体（BEC）的物理特性，特别是在SF-MI跃迁中的自旋变化动力学。我们的研究结果表明，在SF-MI相变之下，一个完善的平均场模型描述了重新规范化自旋依赖相互作用时观测到的数据。有趣的是，这为通过二次塞曼效应和自旋依赖相互作用发生的自旋动力学共振的晶格驱动调谐开辟了新的视角。最后，我们讨论了可以通过我们的设置实现的进一步的晶格配置。
Over recent years, exciting developments in the field of ultracold atoms confined in optical lattices have led to numerous theoretical proposals devoted to the quantum simulation of problems e. g. known from condensed matter physics. Many of those ideas demand experimental environments with non-cubic lattice geometries. In this paper, we report on the implementation of a versatile three-beam lattice allowing for the generation of triangular as well as hexagonal optical lattices. As an important step, the superfluid-Mott insulator (SF-MI) quantum phase transition has been observed and investigated in detail in this lattice geometry for the first time. In addition to this, we study the physics of spinor Bose-Einstein condensates (BEC) in the presence of the triangular optical lattice potential, especially spin changing dynamics across the SF-MI transition. Our results suggest that, below the SF-MI phase transition, a well-established mean-field model describes the observed data when renormalizing the spin-dependent interaction. Interestingly, this opens up new perspectives for a lattice-driven tuning of a spin dynamics resonance occurring through the interplay of the quadratic Zeeman effect and spin-dependent interaction. Finally, we discuss further lattice configurations that can be realized with our setup.