一维光晶格中玻色-爱因斯坦凝聚体的相位涨落测量

J4 ›› 2014, Vol. 31 ›› Issue (1): 56-60.

一维光晶格中玻色-爱因斯坦凝聚体的相位涨落测量

周海龙,朱强,王兵,熊德智

1 中国科学院武汉物理与数学研究所波谱与原子分子物理国家重点实验室，湖北武汉 430071； 2 中国科学院原子频标重点实验室，湖北武汉 430071； 3 中国科学院大学，北京 100049

收稿日期:2013-05-06 修回日期:2013-05-23 出版日期:2014-01-28 发布日期:2013-12-31
通讯作者: 周海龙 (1988 -)硕士生，从事超冷原子物理实验的研究。 E-mail:zhouhl.hust@gmail.com
基金资助:
国家自然科学基金资助(11104322)

Measurement of phase fluctuations of Bose-Einstein condensates in optical lattice

ZHOU Hai-long, ZHU Qiang, WANG Bing, XIONG De-zhi

1 State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, Wuhan Institute of Physics and Mathematics, Chinese Academy of Sciences, Wuhan 430071, China； 2 Key Laboratory of Atomic Frequency Standards (KLAFS), Wuhan Institute of Physics and Mathematics, Chinese Academy of Sciences， Wuhan 430071, China； 3 University of Chinese Academy of Sciences, Beijing 100049， China

Received:2013-05-06 Revised:2013-05-23 Published:2014-01-28 Online:2013-12-31

摘要/Abstract

摘要： 玻色爱因斯坦凝聚体在一维光晶格中的相位涨落是研究量子相变的重要参量。我们在实验上和理论上分别获得了凝聚体从光晶格中释放后的密度分布，通过分析比较两者干涉峰的对比度提取凝聚体在光晶格中的相位涨落。应用这一方法，测量了不同光晶格阱深下凝聚体的相位涨落。当光晶格阱深从最小值5.6ER变化到30.7ER时，相位涨落从δ=0.29π上升到δ=0.69π。

关键词: 量子光学, 一维光晶格, 玻色-爱因斯坦凝聚, 相位涨落

Abstract: For Bose-Einstein condensates in an optical lattice, the phase fluctuation is a significant quantity in the investigation of quantum phase transition. We investigate a method to measure the phase fluctuation by comparing the contrast of interference peaks obtained from experimental absorption images and simulated data sets. Phase variances of condensates in optical lattices with different trap depth are measured by this method. The phase fluctuations increase from δ=0.29π to δ=0.69π when the depth of optical lattice varies from 5.6ER to 30.7ER.

Key words: phase fluctuation

中图分类号:

O562.3

周海龙朱强王兵熊德智. 一维光晶格中玻色-爱因斯坦凝聚体的相位涨落测量[J]. J4, 2014, 31(1): 56-60.

ZHOU Hai-long, ZHU Qiang, WANG Bing, XIONG De-zhi. Measurement of phase fluctuations of Bose-Einstein condensates in optical lattice[J]. J4, 2014, 31(1): 56-60.

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