Title :
Excited state absorption of pump radiation as a loss mechanism in solid-state lasers
Author :
Kliewer, Michael L. ; Powell, Richard C.
Author_Institution :
Dept. of Phys., Oklahoma State Univ., Stillwater, OK, USA
fDate :
8/1/1989 12:00:00 AM
Abstract :
The characteristics of optical pumping dynamics in laser-pumped, rare-earth-doped, solid-state laser materials are investigated by using a tunable alexandrite laser to pump Y3Al5O12 :Nd3+ in an optical cavity. It is found that the slope efficiency of the Nd laser operation depends strongly on the wavelength of the pump laser. For pump wavelengths resulting in low slope efficiencies, intense fluorescence emission is observed from the sample in the blue-green spectral region. This is attributed to the excited-state absorption of pump photons which occurs during radiationless relaxation from the pump band to the metastable state. This type of process is an important loss mechanism for monochromatic pumping of laser systems at specific pump wavelengths
Keywords :
fluorescence; garnets; luminescence of inorganic solids; neodymium; optical losses; optical pumping; solid lasers; yttrium compounds; BeAl2O4; Y3Al5O12:Nd3+; blue-green spectral region; excited-state absorption; intense fluorescence emission; loss mechanism; metastable state; monochromatic pumping; optical cavity; optical pumping dynamics; pump band; pump laser; pump photons; pump wavelengths; radiationless relaxation; slope efficiency; solid-state lasers; tunable alexandrite laser; Absorption; Laser excitation; Neodymium; Optical losses; Optical materials; Optical pumping; Pump lasers; Solid lasers; Stimulated emission; Tunable circuits and devices;
Journal_Title :
Quantum Electronics, IEEE Journal of
