Quantum tunneling of ultracold atoms in optical traps

• Published in: Frontiers of physics 2014-04, Vol.9 (2), p.137-152
• Main Authors: Wu, Jian-Hua, Qi, Ran, Ji, An-Chun, Liu, Wu-Ming
• Format: Article
• Language: English
• Subjects: Abel; Astronomy; Astrophysics and Cosmology; atom-cavity; Atomic; Bose-Einstein condensates; Condensates; Condensed Matter Physics; Decay; Decay rate; High temperature; Josephson effect; Landau-Zener tunneling; Low temperature; Microcavities; Molecular; Optical and Plasma Physics; Optical lattices; Optical traps; Particle and Nuclear Physics; Physics; Physics and Astronomy; quantum tunneling; Quantum tunnelling; Review Article; Ultracold atoms; 光阱; 有效温度; 爱因斯坦凝聚; 物理系统; 超冷原子; 重力作用; 量子隧穿
• ISSN: 2095-0462; 2095-0470
• DOI: 10.1007/s11467-013-0359-z

We review our theoretical advances in quantum tunneling of BoseEinstein condensates in optical traps and in microcavities. By employing a real physical system, the frequencies of the pseudo Goldstone modes in different phases between two optical traps are studied respectivdy, which are tile crucial feature of the non-Abelian Joseptmon effect. When the optical lattices are under gravity, we investigate the quantum tummling in the ＂Wannier-Stark localization＂ regime and ＂Lan（lau Zener tunneling＂ regime. We finally get the total decay rate and the rate is valid over the entire range of temperatures. At high temperatures, we show how the decay rate reduces to the appropriate results for the classical thermal activation. At hltermediate temperatures, the results of tile total decay rate are consistent with the thermally assisted tunneling. At low temperatures, we obtain the pure quantmn tunneling ultimately. And we study the alternating-current and direct-current （ac and de） photonic 3osephson effects in two weakly linked microcavities containing ultracold two-level atones, which allows for direct observation of the effects. This enables new investigations of the effect of maw-body physics in strongly coupled atom-cavity systems and provides a strategy for constructing novel interference devices of coherent photons. In addition, we propose the experimental protocols to observe these quantmn tunneling of Bose- Einstein condensates.