Title :
Design of widely tunable semiconductor lasers and the concept of binary superimposed gratings (BSG´s)
Author :
Avrutsky, Ivan A. ; Ellis, Dave S. ; Tager, Alex ; Anis, Hanan ; Xu, Jimmy M.
Author_Institution :
Dept. of Electr. & Comput. Eng., Toronto Univ., Ont., Canada
fDate :
4/1/1998 12:00:00 AM
Abstract :
We propose a new concept of binary superimposed gratings (BSG´s) as multiwavelength grating reflectors and show it as an effective structural improvement over the existing designs, to both the fabrication process and device performance. We also present a study of key design issues for widely tunable lasers based on grating mirrors with a comb-like reflection spectrum and summarize simple design rules for the grating part of the laser, based on analytical and numerical analysis. The binary supergrating consists of elements of equal size whose refractive index is allowed to be one of two possible values, which are sequenced according to a binary optics formalism to effect a spatial superposition of multiple sets of single-frequency gratings, and its implementation is well within the standard e-beam lithography limits. The calculations of lasing frequency, mode, and side-mode suppression ratio of the tunable laser are formulated and presented along with numerical examples
Keywords :
diffraction gratings; laser mirrors; laser tuning; optical design techniques; refractive index; semiconductor lasers; binary optics formalism; binary supergrating; binary superimposed gratings; comb-like reflection spectrum; device performance; effective structural improvement; equal size; fabrication process; grating mirrors; lasing frequency; lasing mode; multiple sets; multiwavelength grating reflectors; numerical analysis; refractive index; simple design rules; single-frequency gratings; spatial superposition; standard e-beam lithography limits; widely tunable semiconductor laser design; Gratings; Mirrors; Numerical analysis; Optical design; Optical device fabrication; Optical reflection; Optical refraction; Refractive index; Semiconductor lasers; Tunable circuits and devices;
Journal_Title :
Quantum Electronics, IEEE Journal of