Atomic Physics: More Uses for Lasers

R. Cabrera‐Trujillo, J. Jiménez-Mier, A. M.

Carl Wieman, Leo W. Hollberg

Robert J. Thompson

In this paper we will present an overview of the present and future of the Laser Cooling and Atomic Physics (LCAP) program in support of NASA’s Micro-gravity Fundamental Physics program. We will address the role played by the Jet Propulsion Laboratory in developing the core technologies to support the wide variety of science that we envision will be explored by this program.

XuanYang Lai, Qing-yu Cai, Minjie Zhan

In this paper, Bohmian mechanics is applied to intense laser–atom physics. The motion of an atomic electron in an intense laser field is obtained from the Bohm–Newton equation. We find that the quantum potential that dominates the quantum effect of a physical system becomes negligible as the electron is driven far from the parent ion by the intense laser field, i.e. the behavior of the electron smoothly tends towards classical soon after the electron is ionized. Our numerical calculations present direct positive evidence for semiclassical trajectory methods in intense laser–atom physics where the motion of the ionized electron is treated by classical mechanics, while quantum mechanics is needed before the ionization.

W. R. MacGillivray, M. C. Standage

Vladilen S Letokhov

Abstract The invention and development of laser methods for cooling and trapping atoms have led to the advent of the physics of ultracold matter. Low-temperature quantum physics has so far dealt with condensed media, wherein quantum phenomena (superfluidity and superconductivity) usually manifest themselves at temperatures of a few kelvin. Laser cooling and trapping of atoms have made it possible to successively attain millikelvin, microkelvin, and nanokelvin temperatures, at which the de Broglie wavelength of the atoms becomes commensurable with the interatomic separation, even in dilute gases. The interaction of atoms in ultracold dilute gases becomes essentially quantum mechanical. The physics of such quantum gases is more akin to the well-developed physics of condensed matter at low temperatures. It is in essence a boundary field between atomic, laser, and condensed-matter physics. Following the first, pioneering experiments on the Bose–Einstein condensation of alkali-metal atoms, this field has continued to develop at a very fast pace, which can be explained by the vast variety of particles (atoms, isotopes, and molecules) that can be laser cooled and trapped under degeneracy conditions. This is much more than physicists had at their disposal previously (3,4He). Moreover, laser radiation and magnetic fields additionally make it possible to control not only the intrinsic quantum state of the interacting ultracold particle species, but also the interaction of the particles. All this makes the research in the field of quantum gases a great breakthrough, both in atomic–molecular physics and in many-body-interaction physics, which heretofore was the prerogative of low-temperature condensed-matter physics.