Efficient converter of the frequency of ultrashort light pulses to the infrared range

The frequency of ultrashort light pulses was converted to the infrared range for the first time in a T-shaped leucosapphire cell containing an atomic cesium vapor. Electron-stimulated Raman scattering (ESTRS) in this vapor converted ultrashort pulses tunable in the range 522.5–545 nm to the infrared range 2.2–2.66 μm and the maximum quantum efficiency of the process was 20%. The absence of components with critical alignment, the operational simplicity, the relatively low electron ESTRS threshold in respect of the pump intensity, and high parameters of the converted radiation should make this method a promising means for converting the frequency of the second harmonic of picosecond neodymium lasers.