Td. Visser et al., Theory of polarization-dependent amplification in a slab waveguide with anisotropic gain and losses, IEEE J Q EL, 35(2), 1999, pp. 240-249
We analyze the waveguiding properties of a semiconductor slab waveguide amp
lifier in which the gain (i.e., the permittivity) in the quantum well (QW)
is taken to be anisotropic. Losses may be present simultaneously in the cla
dding layers. Using scattering theory, a rigorous integral equation is deri
ved, Our model incorporates the two main causes of polarization sensitivity
of the amplification, viz,, 1) waveguiding and 2) the anisotropic light-ma
tter interaction in the QW, It is determined how much anisotropy is needed
in the QW to get a polarization-insensitive amplification. Also, reflection
coefficients and TE/TM mixing are studied. A comparison between the exact
results and the Born approximation is made. A Green's tensor for a layered
structure with losses is derived.