Tuning indirect-to-direct bandgap of lonsdaleite Si0.5Ge0.5 alloy via compressive strain for optical gain
- Resource Type
- Conference
- Authors
- Mayengbam, Rishikanta; Das, Subhasis; Tan, Chuan Seng; Fan, Weijun
- Source
- 2023 7th IEEE Electron Devices Technology & Manufacturing Conference (EDTM) Electron Devices Technology & Manufacturing Conference (EDTM), 2023 7th IEEE. :1-3 Mar, 2023
- Subject
- Components, Circuits, Devices and Systems
Engineered Materials, Dielectrics and Plasmas
Photonics and Electrooptics
Absorption
Photonic band gap
Discrete Fourier transforms
Metals
Optical coupling
Optical materials
Tuning
Density Functional Theory
SiGe
Bandgap
- Language
This work presents theoretical insights on the electronic bandstructure and optical absorption of lonsdaleite Si 0.5 Ge 0.5 alloy under uniaxial compressive strain. Within the framework of density functional theory (DFT), the electronic and absorption characteristics were calculated by modified Becke-Johnson (mBJ) potential with consideration of spin-orbit coupling (SOC). An indirect-to-direct transition of band gap along with a boost in absorption coefficient is observed in strained alloys, which can be promising for SWIR and mid-IR photonic applications. Optical gain was calculated to demonstrate the applicability of such materials in photonic devices.