Quantum Behavior of Laser Cooled Atoms

R. Ya. Ilenkov, A. V. Taǐchenachev, Valeriy I. Yudin +1 more

We study laser cooling of atoms with narrow-line optical transition, i.e. in regimes when quantum nature of laser-light interactions results significant effect on atom kinetics. We demonstrate the minimum of laser cooing temperature is reached for the light field detuning close to -3 recoil frequency, i.e. is much differ from standard Doppler cooling theory is used for semiclassical description of laser cooling. We define a set of dimensionless parameters that describe the steady state solution of cold atom distribution in laser light and cooling time. The results can be used for analysis an optimal conditions of laser cooling of atoms with narrow lines Ca, Sr and Mg are of interest for optical time standards.

Jean Claude Garreau

Adam M. Kaufman, Brian Lester, Collin Reynolds +5 more

The quantum statistics of atoms is typically observed in the behavior of an ensemble via macroscopic observables. However, quantum statistics modifies the behavior of even two particles. Here, we demonstrate near-complete control over all the internal and external degrees of freedom of two laser-cooled (87)Rb atoms trapped in two optical tweezers. This controllability allows us to observe signatures of indistinguishability via two-particle interference. Our work establishes laser-cooled atoms in optical tweezers as a promising route to bottom-up engineering of scalable, low-entropy quantum systems.

Uday Kumar Khan

Xiang-Yao Wu, Baijun Zhang, H. J. Yang +6 more

J. I. Cirac, Maciej Lewenstein, P. Zoller

We study the dynamics of a system of atoms undergoing laser cooling in a microtrap. Using a simple model, we show that the stationary state of the system can be different from the standard Bose-Einstein distribution. In particular, it can exhibit infinite sequences of phase transitions as a function of laser detuning, as well as multistable behavior. This is due to the combination of quantum statistical phenomena and other effects related to the laser-cooling process.