Wavelength characteristics of chirped quantum dot superluminescent diodes for broad spectrum

Abstract

A chirped InAs quantum dot superluminescent diode both with and without a In0.15Ga0.85As cap layer was fabricated for a broad-band spectrum. This study shows that the cap layer reduces strain and operates as a carrier capturer and that carriers excited by lattice heating-also affect the radiative recombination in the quantum dots (QDs) as well as the cap layer through the characteristic temperature (To). In addition, by surveying peaks of each QD layers, the characteristics of carriers in QDs, such as band-filling effect and the thermal effect, were analyzed, in QDs, and a more effective method for creating a wider spectrum is proposed.