Investigation of the gain of active media utilizing transitions in manganese atoms

An investigation was made of the gain parameters of active media utilizing the y⁶P_j⁰–a⁶D_j and z⁶P_j⁰–a⁶D_j transitions in manganese atoms. The dependence of the gain factor a on the input signal power density was determined. The value of a reached 0.2 cm^–1 for the strongest laser emission line of wavelength 534.1 nm. An investigation was made of the dependences of the saturated gain on the relative timing of the pump pulses of a laser master oscillator and a laser amplifier, and also on the active medium parameters and excitation conditions. A factor of 1.5 increase in the output power was obtained in the amplification regime, compared with that in the oscillation regime, under identical excitation conditions. The output power of the 534.1 and 542 nm lines was 10.6 W, with a single-trip gain of ~ 50, for a 21-mm diameter 650-mm long amplifier.