MIDIT OFD CATS Modelling, Nonlinear Dynamics Optics and Fluid Dynamics Chaos and Turbulence Studies and Irreversible Thermodynamics Risø National Laboratory Niels Bohr Institute and Technical University of Denmark Building 128 Department of Chemistry Building 321 P.O. Box 49 University of Copenhagen DK-2800 Lyngby DK-4000 Roskilde DK-2100 Copenhagen Ø Denmark Denmark Denmark
by Prof. Mario F.S. Ferreira
Department of Physics
University of Aveiro
3800 Aveiro,
Portugal
MIDIT-seminar 415
Friday August 28, 1998, 14.00 h
at MIDIT, IMM Building 305, room 027
Abstract: A theorectical model is presented to describe the tuning, frequency noise, and modulation characteristics of tunable DBR lasers with two active and two passive sections. Among other results, it is shown that a nearly flat red-shifted FM response over several gigahertz can be obtained by nonuniform current injection and modulation of the lower carrier density section in the active region. Increasing the tuning current through the passive sections enhances the FM response. However, a higher FM efficiency is generally accompaned by a larger spectral linewidth. Some design optimization criteria for this type of lasers are pointed out and discussed.