Cyj. Chu et H. Ghafourishiraz, ANALYSIS OF GAIN AND SATURATION CHARACTERISTICS OF A SEMICONDUCTOR-LASER OPTICAL AMPLIFIER USING TRANSFER-MATRICES, Journal of lightwave technology, 12(8), 1994, pp. 1378-1386
The transfer matrix method (TMM) has been applied to analyze the gain
and saturation characteristics of semiconductor laser optical amplifie
rs. This method approximates the amplifier cavity by dividing it into
M discrete subsections, and TMM has been applied to analyze the stepwi
se longitudinal field distribution at each subsection along the amplif
ier cavity. By incorporating also the carrier rate equations into the
analysis, it has been shown that the approximation can accurately desc
ribe the carrier density and longitudinal field distribution along the
amplifier cavity if M is sufficiently large (i.e., the size of each s
ubsection is about an order of magnitude of one wavelength of the inpu
t signal). By assuming that the amplifier is biased below oscillation
threshold such that the contribution of spontaneous emissions to the g
ain characteristics can be neglected, we have shown that our proposed
method yields a fast and efficient algorithm in analyzing the gain and
saturation characteristics of laser amplifiers. We have compared the
results produced by our method to those analyzed using the average pho
ton density (AVPD) approximation technique, as well as to experimental
results on a 1.5-mu m buried heterostructure semiconductor laser ampl
ifier.