Laser fluorescence inhibition at the interface of a glass and an optically thick Cs vapor

摘要

A fluorescence radiation inhibition has been observed by absorption of a laser beam at a resonance of 852 nm at the interface of a Pyrex cell containing optically thick Cesium vapor. One observes a hole of GHz magnitude at the center of the retro-fluorescence signal associated with the lines of hyperfine structure 6~2P_(3/2)-6~2S_(1/2) (F=4,3). This phenomenon of inhibition, similar to a self-reversal of spectral lines, is found in the radiation generated by pooling effect. It occurs without a significant change in the absorption rate of laser energy. This is attributed to a coupling between atoms excited to 6~2P_(3/2) by laser pumping and a deposit of Cesium of atomic dimensions on the glass. At resonance, an important proportion of the atoms excited by the laser is in the vicinity of a thin conducting film. the non-radiating transformation process of the atomically excited energy to thermal energy is therefore favored. The interface lit by a monochromatic laser diode acts as a stop band filter and as a secondary luminous source. The width of the filter at half-height is proportional to the density of the atomic vapor. Sub-Doppler effects in inhibition spectral band have been observed. We present new experimental results and a phenomenon-related study of fluorescence inhibition induced by interfaced laser.