Atom optics with hollow optical systems

Kwanil Lee, Jong-An Kim, Kihwan Kim +7 more

Renwang Mu, LU Jun-fa, Shuwu Xu +2 more

We propose a new scheme to form 1D or 2D arrays of hollow optical microtraps for cold atoms, molecules, or microscopy particles on a chip by using an optical system composed of a four-step phase grating and a 2D array of microlenses. We calculate the intensity distribution of the 2D array of the hollow optical microtraps and its optical potential for 85Rb atoms and discuss its potential applications in atom and molecule optics. Our study shows that when our optical system is illuminated by a 1 W Ti:Sapphire laser, 103 hollow optical microtraps can be generated. Each optical microtrap has a small trapping volume and a high effective intensity, and its intensity gradient and the optical dipole potential for 85Rb atoms can reach 167 μK. Characteristic parameters of each optical microtrap can be changed by adjusting the parameters of our optical system, which can be used to satisfy real needs of various experiments to manipulate and control cold atoms, molecules, or microscopy particles.

Ji Xian-Ming, Renwang Mu, Jinghuai Fang +2 more

In this paper, we propose a new scheme to generate a dark hollow-beam, which includes dark hollow-beam optical pipe and hollow-beam optical dipole trap, through using a system composed of a four steps phase plate and a spherical lens. This kind of light beam can be used to focus, guide and trap the cold atom. We also calculate the intensity distributing and characteristic parameters of a dark hollow-beam and the optical dipole potential which manipulate the cold atoms of 85Rb. At last, we analyze and demonstrate the experimental feasibility of the scheme.

S. L. Rolston, William D. Phillips

V. I. Balykin

Ji Xian-Ming, Renwang Mu, Yin Jianping +1 more

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 array of surface hollow optical traps with 104 micro-wells will be generated in an area of 1cm2. 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.