一种新颖的表面空心微光阱阵列

A novel array of surface hollow optical micro-traps

提出了采用四台阶相位光栅与微透镜阵列组合产生一种新颖的表面空心微光阱阵列的方案,研究了表面空心微光阱阵列的光强分布,计算了相应的光学囚禁势,并讨论了该微光阱阵列在原子分子光学中的潜在应用.研究表明当用1W的YAG激光照射时,在1cm2面积上可产生近104个空心光阱,每个光阱具有较小的囚禁体积和较大的有效光强及其强度梯度,对85Rb原子的光学囚禁势可达190μK.如此深的光阱足以囚禁冷原子或冷分子,并可用于实现全光型原子或分子玻色-爱因斯坦凝聚,甚至制备新颖的光学晶格等.

In this paper, we propose a new scheme to form an array of surface hollow optical micro-traps for cold atoms （or molecules） by using a phase grating with four phase steps and an array of microlens, study the intensity distribution of 2D array of surface hollow optical micro-traps, and calculate the corresponding optical potential for cold ^85Rb atoms, and discuss some potential applications of our hollow micro-trap array in atom and molecule optics. Our study shows that when our grating-lens system is illuminated by YAG laser with a power of 1W, a 2D army of surface hollow optical traps with 10^4 micro-wells will be generated in an area of 1 cm^2. Each optical trap has some novel characteristics, such as smaller trapping volume, higher effective intensity and its intensity gradient. The corresponding optical potential for trapped ^85Rb atoms can reach 190μK, which is high enough to trap cold atoms or cold molecules, and can be used to realize an all-optical atomic and molecular Bose-Einstein condensations, even to prepare novel optical lattices, and so on.