Photoluminescence study of interband transitions in few-layer, pseudomorphic, and strain-unbalanced Ge/GeSi multiple quantum wells

Abstract

In this paper we investigate the structural and optical properties of few strain-unbalanced multiple Ge/GeSi quantum wells pseudomorphically grown on GeSi reverse-graded substrates. The obtained high epitaxial quality demonstrates that strain symmetrization is not a mandatory requirement for few quantum-well repetitions. Photoluminescence data, supported by a thorough theoretical modeling, allow us to unambiguously disentangle the spectral features of the quantum wells from those originating in the virtual substrate and to evaluate the impact on the optical properties of key parameters, such as quantum confinement, layer compositions, excess carrier density, and lattice strain. This detailed understanding of the radiative recombination processes is of paramount importance for the development of Ge/GeSi-based optical devices.

References in corpus (6)

• Low-threshold optically pumped lasing in highly strained Ge nanowires
• Temperature-dependent photoluminescence characteristics of GeSn epitaxial layers
• Giant g factor tuning of long-lived electron spins in Ge
• Disentangling nonradiative recombination processes in Ge micro-crystals on Si substrates
• Ge Microdisk with Lithographically-Tunable Strain using CMOS-Compatible Process
• Spin-dependent direct gap emission in tensile-strained Ge films on Si substrates

Cited by in corpus (2)

• Intersubband transition engineering in the conduction band of asymmetric coupled Ge/SiGe quantum wells
• Quantum spin Hall phase in GeSn heterostructures on silicon