Sc. Fleming, ACCURATE ANALYTIC EXPRESSIONS FOR GAIN IN A PR3- ZBLAN FIBER AMPLIFIER USING MODIFIED GAUSSIAN FIELD FUNCTIONS( ), IEEE journal of quantum electronics, 30(2), 1994, pp. 280-283
Pr3+: ZBLAN fiber amplifiers are likely to be important components for
1.3 mum fiber systems. Efficient amplifiers require high DELTAn small
-core fibers. Expressions for the gain of such amplifiers have been de
rived. To obtain useful analytic expressions, it is necessary to appro
ximate the mode field distribution with a simple function. For this ty
pe of fiber, the usual Gaussian is not a good approximation, resulting
in poor predictions of amplifier performance. This paper describes th
e use of a modified Gaussian function which better approximates the mo
de field distribution. It is shown by comparison to a full numerical s
olution that the analytic expressions based on this modified Gaussian
are significantly more accurate.