Self-assembling quantum dots for optoelectronic devices on Si and GaAs

Investigation of strain in self-assembled multilayer InAs/GaAs quantum dot heterostructures

“…Also, the use of barrier in between the QD layers is very much needed as a strain reducing layer (SRL) to release the tensile strain in the structure and also to tune the emission from the heterostructure towards the telecommunication wavelength range [12,13]. Thus strain plays an important role in the growth of multilayer heterostructure [14][15][16]. Hence it is essentially important to probe strain in these system for the clear understanding of the growth of self-assembled defect-free multilayer QDs and causes of structural correlation in such system.…”

Study on carrier trapping and emission processes in InAs/GaAs self-assembled quantum dots by varying filling pulse width during DLTS measurements

“…Due to low dimensionality and hydrogen-like potential, carriers in QDs have quantized energy states like electrons in atomic potentials [1,2]. GaAs and InP based systems of InAs self-assembled QDs have received great attention due to their compatibility with 1.55 µm fiber-optics technology [3,4]. Since InAs and GaAs have a large lattice constant mismatch, InAs QDs can be easily self-assembled on GaAs substrates in Stranski-Krastanov (SK) growth mode [5,6].…”

High resolution STEM of quantum dots and quantum wires

“…Other examples of electron microscopy studies of these structures have included determination of their shape and size (e.g. Eberl et al, 2001;Sales et al, 2010;Liu et al, 2000;Inoue et al, 2008), chemical composition (in particular intermixing at the interface) (Zhi et al, 2001;Wang et al, 2006), changes introduced due to overgrowth with a matrix (Molina et al, 2007b;Kadkhodazadeh et al, 2011a;Sakuma et al, 2005) and strain measurement (Cooper et al, 2011). Since these structures are typically 1.…”