Title :
Analysis of TM-polarized DFB laser structures with metal surface gratings
Author :
Finger, N. ; Schrenk, W. ; Gornik, E.
Author_Institution :
Inst. of Solid State Electron., Wien Univ., Austria
fDate :
7/1/2000 12:00:00 AM
Abstract :
An analysis of distributed feedback (DFB) laser structures with metallized surface grating structures in TM polarization is presented. The modal properties of these structures are described using coupled-mode theory where the coupling coefficients are derived from rigorously computed on-resonant Floquet-Bloch solutions of the waveguide grating problem. Based on this theory, first- and second-order DFB quantum cascade laser structures operating at a wavelength of 10 /spl mu/m are investigated numerically. We show that, utilizing a metal stripe grating structure, second-order laser structures are feasible showing efficient surface emission, whereas radiation into the substrate is strongly suppressed. The fraction of stimulated emission power being emitted via the surface can be as high as 17.5% whereas a low threshold gain of 20 cm/sup -1/ is maintained.
Keywords :
coupled mode analysis; diffraction gratings; distributed feedback lasers; laser modes; laser theory; light polarisation; stimulated emission; surface emitting lasers; 10 micron; Floquet-Bloch analysis; TM polarization; coupled-mode theory; distributed feedback laser; metal surface grating; quantum cascade laser; stimulated emission; surface emission; threshold gain; waveguide grating structure; Distributed feedback devices; Gratings; Laser feedback; Laser theory; Metallization; Polarization; Quantum cascade lasers; Surface emitting lasers; Waveguide lasers; Waveguide theory;
Journal_Title :
Quantum Electronics, IEEE Journal of
