Accession Number : ADA321852

Title :   (DURIP-95) Nano-Kelvin Cooling of Dense Atoms for an Ultra-Stable Fountain Atomic Clock.

Descriptive Note : Final rept. 1 Sep 95-30 Aug 96,

Corporate Author : MASSACHUSETTS INST OF TECH CAMBRIDGE RESEARCH LAB OF ELECTRONICS

Personal Author(s) : Ezekiel, Shaoul ; Shahriar, Selim

PDF Url : ADA321852

Report Date : FEB 1997

Pagination or Media Count : 6

Abstract : With the funding provided under this grant, we have procured equipments for creating a sample of 87Rb atoms with ultracold temperature (35 nano-Kelvin) and high density (10(exp 12 /sq cm), using Raman cooling via velocity selective coherent population trapping. We have already been able to create a magneto-optic trap (MOT) of 87Rb atoms, loaded from background rubidium vapor inside the trap chamber. We have achieved a density close to 10(exp 12) /sq cm, at a temperature of 80 mu-K, which is typical of such a trap. The next step is to load the trap from a chirp-slowed atomic beam, and use a repumping beam which is dark at the center. This is expected to increase the density to about 10(exp 12) /sq cm. We will then Raman- cool the sample to about 35 nano-Kelvin, thus yielding a sample for a rubidium fountain clock. The fountain clock loaded from this source is expected to have a short term accuracy that is more than two orders of magnitude better than existing cesium fountain, which are already a factor of two better than existing cesium beam clocks used as primary frequency standards.

Descriptors :   *ATOMIC CLOCKS, MAGNETOOPTICS, ACCURACY, ENERGY TRANSFER, TRAPPING(CHARGED PARTICLES), COOLING, RAMAN SPECTRA, RUBIDIUM, METAL VAPORS.

Subject Categories : Test Facilities, Equipment and Methods
      Electricity and Magnetism

Distribution Statement : APPROVED FOR PUBLIC RELEASE