To simulate blackbody radiation frequency shift in cesium fountain frequency standard with CO/sub 2/ laser

An experimental scheme to simulate the blackbody radiation (BBR) frequency shift with carbon dioxide (CO
₂
) laser in cesium fountain frequency standard is proposed. The alternative (ac) electric field from a CO
₂
laser with 10.6 mum wavelength causes the similar ac Stark shift of the clock transition frequency, but with much higher intensity than BBR power intensity at about room temperature. This scheme provides a simple, new method for measuring the BBR frequency shift in fountain clock. It provides the possibility to explain the difference of BBR shifts in Cs fountain clocks between two measurement methods