2-μm single longitudinal mode GaSb-based laterally coupled distributed feedback laser with regrowth-free shallow-etched gratings by interference lithography
Yang Cheng-Ao1, 2, Zhang Yu1, 2, Liao Yong-Ping1, 2, Xing Jun-Liang1, 2, Wei Si-Hang1, 2, Zhang Li-Chun1, 2, Xu Ying-Qiang1, 2, Ni Hai-Qiao1, 2, Niu Zhi-Chuan1, 2, †,
       

SEM picture of LC-DFB laser with second-order grating fabricated by interference lithography. (a) Top view of the laser after the deposition of p-side metal (Ti/Pt/Au), (b) sectional view of grating after dry etching.