Emission of direct-gap band in germanium with Ge-GeSn layers on one-dimensional structure.
In our experiment, it was observed that the emission of direct-gap band in germanium with Ge-GeSn layers on one-dimensional (1D) structure. The results of experiment and calculation demonstrate that the uniaxial tensile strain in the (111) and (110) direction can efficiently transform Ge to a direct bandgap material with the bandgap energy useful for technological application. It is interested that under the tensile strain from Ge-GeSn layers on 1D structure in which the uniaxial strain could be obtained by curved layer (CL) effect, the two bandgaps EΓg and ELg in the (111) direction become nearly equal at 0.83 eV related to the emission of direct-gap band near 1500 nm in the experiments. It is discovered that the red-shift of the peaks from 1500 nm to 1600 nm occurs with change of the uniaxial tensile strain, which proves that the peaks come from the emission of direct-gap band.
State Key Laboratory of Surface Physics, Key Laboratory of Micro and Nano Photonic Structures (Ministry of Education) and Department of Physics, Fudan University, Shanghai 200433 (China).
Zhong-Mei
ZM
Huang
Institute of Nanophotonic Physics, Guizhou University, Guiyang 550025 (China).
Wei-Qi
WQ
Huang
State Key Laboratory of Environmental Geochemistry Institute of Geochemistry, Chinese Academy of Science Institute of Geochemistry, Guiyang 550003 (China).
Shi-Rong
SR
Liu
Institute of Nanophotonic Physics, Guizhou University, Guiyang 550025 (China).
Tai-Ge
TG
Dong
Institute of Nanophotonic Physics, Guizhou University, Guiyang 550025 (China).
Gang
G
Wang
Institute of Nanophotonic Physics, Guizhou University, Guiyang 550025 (China).
Xue-Ke
XK
Wu
State Key Laboratory of Environmental Geochemistry Institute of Geochemistry, Chinese Academy of Science Institute of Geochemistry, Guiyang 550003 (China).
Cao-Jian
CJ
Qin