Original 1997 paper on Er-doped waveguide lasers

I.Rigorous model based on an arbitrary rare-earth-doped laser host with multiple energy levels

	Time-dependent scalar wave equations
	Time and space-dependent laser rate equations
	For complete sets of equations, see Veasey,D.L.,et.al."Time-dependent Modelling of Erbium-Doped Waveguide Lasers in Lithium Niobate Pumped at 980 and 1480 nm,"J.Quantum Electronics,Vol.33,No.10,October 1997.

II. Features of the Model

	Model contains rate equations for 4 Erbium energy levels
	Single forward and backward wave equations for the laser and pump signals
	Elliptical electric fields are estimated using a Gaussian distribution functio
	Emission and absorption rates used for determining ion specie concentration changes are functions of the electric fields, pump power and energy level constants.

III. Initial Use of the Model

	To optimize laser design for length and reflectance, by running the code for series of different cases.
	To optimize laser design for threshold and output power as a function of pumping power, laser length, and glass parameters.
	To model Q-switch lasers by assuming a very thin absorber at the end facet.