Title :
Analysis of gain dynamics in Pr/sup 3+/-doped fluoride fiber amplifiers
Author_Institution :
Inst. fur Hochfrequenztech., Tech. Univ. Braunschweig, Germany
fDate :
3/1/1995 12:00:00 AM
Abstract :
A large-signal model for a four-level laser system which includes time variation effects has been used to study low frequency response characteristics, two-channel crosstalk and transient effects in praseodymium-doped fluoride fiber amplifiers (PDFFA). Pump power modulation results in a low-pass transfer of modulation to signals amplified in the PDFFA. Low-frequency compression of the PDFFA input/output signal transfer characteristic has been observed. Due to a relatively long lifetime of the /sup 1/G/sub 4/ metastable level, multichannel crosstalk lower than 30 dB has been calculated for modulation frequencies higher than 600 kHz. Response of the PDFFA toward a low-frequency signal square pulse exhibits a characteristic overshoot that originates from the PDFFA saturation by the amplified signal.<>
Keywords :
aluminium compounds; barium compounds; fibre lasers; frequency response; lanthanum compounds; laser theory; metastable states; modelling; optical crosstalk; optical fibre communication; optical modulation; optical pulse compression; optical pumping; optical saturation; praseodymium; radiative lifetimes; sodium compounds; zirconium compounds; /sup 1/G/sub 4/ metastable level; 600 kHz; PDFFA saturation; Pr/sup 3+/-doped fluoride fiber amplifiers; amplified signal; four-level laser system; gain dynamics; input/output signal transfer characteristic; large-signal model; low frequency response characteristics; low-frequency compression; low-frequency signal square pulse; low-pass transfer; modulation frequencies; multichannel crosstalk; praseodymium-doped fluoride fiber amplifiers; pump power modulation; relatively long lifetime; time variation effects; transient effects; two-channel crosstalk; Absorption; Crosstalk; Equations; Gain; Laser excitation; Numerical models; Optical fiber amplifiers; Optical fiber communication; Pulse modulation; Pump lasers;
Journal_Title :
Photonics Technology Letters, IEEE
