Close

Search

Search Menu
Photonics Media Photonics Buyers' Guide Photonics EDU Photonics Spectra BioPhotonics EuroPhotonics Industrial Photonics Photonics Showcase Photonics ProdSpec Photonics Handbook
More News
SPECIAL ANNOUNCEMENT
2016 Photonics Buyers' Guide Clearance! – Use Coupon Code FC16 to save 60%!
share
Email Facebook Twitter Google+ LinkedIn Comments

Cavity-Cooling Technique Cools Single Atoms

Photonics Spectra
Apr 2004
At Max Planck Institut für Quantenoptik in Garching, Germany, researchers have developed an optical means of cooling single atoms that is at least five times faster than current techniques. Moreover, the approach, which they reported in the March 4 issue of Nature, might enable the cooling of an atom with a stored qubit without disturbing the quantum information, making it suitable for use in novel experiments in quantum information technology.

The technique employs single rubidium-85 atoms in a 120-µm-long high-finesse resonator that is excited by a weak, near-resonant 780.2-nm probe and a stronger, far-detuned 785.3-nm dipole laser. Rather than cooling by spontaneous emissions from the atom, the setup cools by exploiting the strong coupling between the atom and the cavity radiation. As the atom moves away from a node in the standing wave generated in the resonator, the index of refraction of the single-atom medium decreases. As a result, the frequencies of the cavity and of the photons escaping from it increase, carrying off some of the kinetic energy of the atom in the process.

The researchers suggest that because the technique does not need to excite the target to be cooled, it may be used with molecules, Bose-Einstein condensates or with qubit-carrying atoms.


GLOSSARY
resonator
A volume, bounded at least in part by highly reflecting surfaces, in which light of particularly discrete frequencies can set up standing wave modes of low loss. Often, in laser work,the resonator contains two facing mirrors that may either be flat (Fabry-Perot resonator) or have some spherical curvature, which together bind the lasing material that is referred to as the gain medium, and hence the optical cavity of a laser is where lasing occurs.  
Comments
Terms & Conditions Privacy Policy About Us Contact Us
back to top

Facebook Twitter Instagram LinkedIn YouTube RSS
©2016 Photonics Media
x Subscribe to Photonics Spectra magazine - FREE!