Atmospheric and Oceanic Optics
Amplified Spontaneous Emission on Sodium D-lines Using Nonresonant Optical Pumping
Timofey D. Petukhov, Gennadiy S. Evtushenko, Evgeny N. Telminov
Abstract
We describe experiments on the excitation of amplified spontaneous emission on the D -lines of sodium ( D 2 = 588.9 nm; D 1 = 589.6 nm) with longitudinal optical pumping with a large detuning from the D 2 line toward shorter wavelengths. The radiation spectra are measured, showing gain on both lines, at a Na concentration of (1–5) × 10 14 cm –3 , buffer gas (helium) pressure of 600 Torr at the working temperature, and pumping power density of more than 1.5 MW/cm 2 . The time characteristics show that the output radiation varies versus the concentration of sodium atoms in the active medium. The dependences of radiation absorption at the D -lines of sodium on the concentration of Na atoms and buffer gas pressure are given.