Electrically injected GeSn lasers with peak wavelength up to 2.7 μm
Abstract
GeSn lasers enable the monolithic integration of lasers on the Si platform using all-group-IV direct-bandgap material. The GeSn laser study recently moved from optical pumping into electrical injection. In this work, we present explorative investigations of GeSn heterostructure laser diodes with various layer thicknesses and material compositions. Cap layer material was studied by using Si 0.03 Ge 0.89 Sn 0.08 and Ge 0.95 Sn 0.05 , and cap layer total thickness was also compared. The 190 nm SiGeSn-cap device had threshold of 0.6 kA / cm 2 at 10 K and a maximum operating temperature ( T max ) of 100 K, compared to 1.4 kA / cm 2 and 50 K from 150 nm SiGeSn-cap device, respectively. Furthermore, the 220 nm GeSn-cap device had 10 K threshold at 2.4 kA / cm 2 and T max at 90 K, i.e., higher threshold and lower maximal operation temperature compared to the SiGeSn cap layer, indicating that enhanced electron confinement using SiGeSn can reduce the threshold considerably. The study of the active region material showed that device gain region using Ge 0.87 Sn 0.13 had a higher threshold and lower T max , compared to Ge 0.89 Sn 0.11 . The performance was affected by the metal absorption, free carrier absorption, and possibly defect density level. The maximum peak wavelength was measured as 2682 nm at 90 K by using Ge 0.87 Sn 0.13 in gain regions. The investigations provide directions to the future GeSn laser diode designs toward the full integration of group-IV photonics on a Si platform.
Document Details
- Document Type
- Pub Defense Publication
- Publication Date
- Dec 21, 2021
- Source ID
- 10.1364/prj.443144
Entities
People
- Baohua Li
- Chen-wei Wu
- Greg Sun
- Gregory J. Salamo
- Grey Abernathy
- Guo-En Chang
- Huong Q Tran
- Jake Bass
- Jifeng Liu
- Joe Margetis
- John Tolle
- Joshua M. Grant
- Richard Soref
- Shui-Qing Yu
- Solomon Ojo
- Sylvester Amoah
- Wei Du
- Yiyin Zhou
- Yong-hang Zhang
- Yuanhao Miao
Organizations
- Air Force Office of Scientific Research
- Arizona State University
- Dartmouth College
- National Chung-Cheng University
- University of Arkansas
- University of Massachusetts Boston
- Wilkes University