Computers in Physics
Numerical simulations of an atomic beam focused by an optical potential
T. Kidan, Joan Adler, A. Ron
Abstract
We present a model to describe the behavior of an atomic beam in a focusing experiment and discuss its implementation. Such modeling is relevant to the development of atom lithography. For simplicity, the light-atom interaction may be treated as a conserving potential (neglecting spontaneous emission) so that the Schrödinger equation is sufficient for a description of the problem. We start from a two-dimensional time-dependent Schrödinger equation that is reduced to a one-dimensional equation by a paraxial approximation, and then solved iteratively via Padé approximation. The solution is implemented in an interactive routine with Matlab(5.x) to compute and visualize the atomic wave packet development as it propagates through the laser light optical potential. We present examples of our implementation, starting with cases that have known analytic solutions such as propagation of the atomic wave packet through free space and through a parabolic potential. We also present a case that does not have a simple analytic solution, namely the propagation of the atomic wave packet through a focusing optical potential, which has a Gaussian profile in the propagation direction and a parabolic profile in the perpendicular direction. © 1998 American Institute of Physics.