PROCEEDINGS ARTICLE | November 21, 2007

Proc. SPIE. 6781, Passive Components and Fiber-based Devices IV

KEYWORDS: Refractive index, Quantum wells, Waveguides, Cladding, Dielectrics, Quantum efficiency, Wave propagation, Planar waveguides, Waveguide modes, Phase shifts

Based on the Helmholtz's equation and energy conservation law for the travelling wave field, the actual wave function
for the TE travelling wave in the inhomogeneous dielectric is recommended, the original field distribution functions of
the TE mode in symmetrical planar waveguide core layer and cladding layers are suggested. Moreover, the virgin phase
shift for total reflection effect at the turning point is proposed, the eigen equation of a new improved WKB method for
the symmetrical planar waveguide is given. As the concept of phase delay for optical wave in the dielectric and the new
improved WKB method are engaged, the multiple quantum wells planar waveguide is considered as an equivalent of the
triplex layer waveguide, a new method for analyzing the symmetrical multiple quantum wells planar waveguide is put
forward. Several approximate formulas for computing the effective refractive index, the normalized frequency and mode
field distribution are presented. Then, found on the maximal matching efficiency method for the mode field distributions,
the expression of Gaussian approximation for the mode field distribution of single mode symmetrical multiple quantum
wells planar waveguide is present. As an example, the normalized field distributions of GaAs/GaAlAs symmetrical
multiple quantum wells planar waveguide is referred.