THEORY OF OPTICAL MODES IN SEMICONDUCTOR MICRODISK LASERS

A method for the calculation of optical modes in disk-like resonant ca vities is presented. The eigenvalue equation for resonant wavelengths and threshold optical gain as well as the optical field distribution i s established. The characteristics of the optical modes in microdisk l asers are studied using this method. Numerical calculations are carrie d out for some long wavelength microdisk lasers. The theoretical analy ses and numerical results show that the optical modes in a microdisk l aser with a very small thickness can be approximately classified into transverse electric and transverse magnetic modes, but the lasing mode s and other lower threshold modes are transverse electric polarized, a nd a spontaneous emission coefficient between 0.2 and 0.3 can be achie ved in long wavelength semiconductor microdisk lasers. The possibility of a microdisk laser to lase in a surface emitting mode is also demon strated. (C) 1997 American Institute of Physics.