Title :
Small-divergence singlemode emitting tapered distributed-feedback quantum cascade lasers
Author :
Zhang, Wensheng ; Wang, Lingfeng ; Li, Luoqing ; Liu, Jiangchuan ; Liu, Feng-Qi ; Wang, Zhen
Author_Institution :
Key Lab. of Semicond. Mater. Sci., Chinese Acad. of Sci., Beijing, China
Abstract :
A tapered distributed feedback quantum cascade laser emitting at ?? ~ 8.1 ??m is reported. Utilising a tapered waveguide structure with a surface metal grating, the device exhibited singlemode operation over the temperature range of 100 to 214 K, with sidemode suppression ratio > 20 dB and a nearly diffraction limited far-field beam divergence angle of 5.4??.
Keywords :
molecular beam epitaxial growth; quantum cascade lasers; small-divergence singlemode emitting tapered distributed-feedback quantum cascade lasers; surface metal grating; temperature 100 K to 214 K;
Journal_Title :
Electronics Letters
DOI :
10.1049/el.2010.0554
