Title :
Low-threshold room-temperature operation of injectorless quantum-cascade lasers: influence of doping density
Author :
Friedrich, A. ; Huber, Claire ; Boehm, G. ; Amann, M.-C.
Author_Institution :
Walter-Schottky Inst., Tech. Univ. Muenchen, Garching
Abstract :
The influence of the doping density in the active sections of InP-based injectorless quantum cascade lasers, emitting at 6.8 mum, is investigated. The doping sheet density is varied in the range 2.5-8.6times1010 cm-2. Lasing is observed in the whole range, with a threshold current density as low as 1.2 kA/cm2 at 300 K for the smallest doping sheet density of 2.5times10 10 cm-2. Further improvement has been made by additionally increasing the number of periods in the active region from 40 to 60. With the same doping level of 2.5times1010 cm-2 record low threshold current densities of 0.73 kA/cm2 at 300 K were achieved
Keywords :
III-V semiconductors; aluminium compounds; current density; gallium arsenide; indium compounds; quantum cascade lasers; semiconductor doping; 300 K; InP; current density; doping density; doping sheet density; quantum cascade lasers;
Journal_Title :
Electronics Letters