Blue laser induced bright red fluorescence in hot cesium vapor

TL;DR

This study demonstrates laser-induced fluorescence in cesium vapor, showing how 456 nm laser radiation can generate bright red fluorescence at 852 nm, with potential applications in optical filtering and wavelength conversion.

Contribution

It presents the first observation of laser-induced fluorescence at 852 nm in cesium vapor using 456 nm excitation, highlighting temperature-dependent behavior and spectral self-conversion effects.

Findings

Maximum fluorescence at 130°C

Significant decrease in fluorescence around 300°C

Effective conversion of 456 nm to 852 nm radiation

Abstract

We have observed laser-induced fluorescence using 456 nm laser radiation, resonant with the 6S1/2-7P3/2 transition in Cs atoms. It includes red emission lines in the range of 580-730 nm and a prominent line at 852 nm corresponding to the 6P3/2-6S1/2 transition. A T-shaped all-sapphire cell with a length of 1 cm, containing Cs atomic vapor and capable of being heated up to 500 oC, was used. The laser-induced fluorescence (LIF) power at 852 nm was investigated as a function of the cell temperature. The maximum LIF power was achieved at 130 oC, while a significant decrease was observed around 300 oC. At 130 oC, the Doppler-broadened LIF spectrum at 852 nm exhibited self-conversion, resulting in the formation of two distinct peaks within the spectrum. The LIF power at 852 nm was also studied as a function of the 456 nm radiation power. The Cs cell demonstrated potential as an efficient optical filter and down-converter, effectively transforming 456 nm radiation into 852 nm radiation.