Analysis of reflection properties of Bragg mirror with oxide window

In present high-reflectivity laser reflectors are usually made of number of quarter-wavelength Bragg stacks. This is done for necessary reflectivity and operating range. Because of the periodicity of the quarter-wavelength structure, these reflectors have non-zero reflection delay and phase dispersion. The dispersion leads to the impulse widening and distortion. The delay leads to the increasing of the pulse traveltime in the resonator. The investigations of such phenomena in laser reflectors are extremely important in VCSELs with oxide window because of their application in data transfer systems with high bit rate. The oxide window has an influence on the electromagnetic field distribution is laser cavity and it can be the source of the additional dispersion. That's why the analysis of Bragg mirrors with oxide window reflectivity is the topical problem.