Title :
High-efficiency, single-lobe surface-emitting DFB/DBR lasers
Author :
Witjaksono, G. ; Li, S. ; Botez, D.
Author_Institution :
Dept. of Electr. & Comput. Eng., Wisconsin Univ., Madison, WI, USA
Abstract :
Recently, it has been shown (Witjaksono and Botez, Appl. Phys. Lett., vol. 78, p. 4088, 2001) that DFB/DBR devices with central (grating) phase shift around π fundamentally favor lasing in an orthonormal, single-lobe beam pattern. Here, we present a study of the novel device´s intermodal discrimination and efficiency as a function of the grating duty cycle; the optimization of the device for maximum efficiency; and the first experimental realization of a semiconductor grating incorporating a π phase shift. External differential quantum efficiencies as high as 62% can be obtained from devices with 22 cm-1 threshold gain
Keywords :
diffraction gratings; distributed Bragg reflector lasers; distributed feedback lasers; laser cavity resonators; optimisation; quantum well lasers; semiconductor device measurement; surface emitting lasers; 62 percent; DFB/DBR devices; InGaAs-InGaAsP-InGaP-GaAs; central grating phase shift; differential quantum efficiencies; efficiency; grating duty cycle; intermodal discrimination; lasing; optimization; orthonormal single-lobe beam pattern; semiconductor grating; single-lobe surface-emitting DFB/DBR lasers; threshold gain; Distributed Bragg reflectors; Fabrication; Gallium arsenide; Gold; Gratings; Holography; Lithography; Phased arrays; Resists; Surface emitting lasers;
Conference_Titel :
Lasers and Electro-Optics Society, 2001. LEOS 2001. The 14th Annual Meeting of the IEEE
Conference_Location :
San Diego, CA
Print_ISBN :
0-7803-7105-4
DOI :
10.1109/LEOS.2001.969210
