DFG Research Grant: Terahertz Quantum Cascade Lasers Based on Interface Roughness Engineering in InGaAs/InAlAs Heterostructures on InP
There are two scattering mechanisms in quantum cascade lasers (QCLs) that give rise to a parasitic (non-radiative) current in the transition region, thus limiting the efficiency: inelastic longitudinal-optical (LO)-phonon assisted scattering and elastic interface-roughness (IFR) assisted scattering. The IFR scattering can be reduced by reducing the product of conduction band offset and the electron probability via using a lower and thicker barrier in the middle of transition region instead of traditional thin and high barrier. The IFR scattering can be also reduced by making the interfaces less rough by growing the structures on off-cut substrates.
The goal of the proposed research is to study two complementary approaches to manipulate the interface roughness (IFR) scattering in InGaAs/InAlAs THz quantum cascade lasers as a way to improve the high-temperature performance of InGaAs/InAlAs THz QCL.
Masselink, W. Ted Ph. D. Prof. (Details) (Experimental Physics / Elementary Stimulation and Transport in Solids)
Financer
DFG: Sachbeihilfe
Duration of project
Start date: 06/2019
End date: 05/2022
Research Areas
Electrical Engineering and Information Technology, Electronic Semiconductors, Components, Circuits, Systems, Engineering Sciences
Research Areas
Elektronik