The fundamental understanding of quantum dot (QD) growth mechanism is essential to improve QD based optoelectronic devices. The size, shape, composition, and density of the QDs strongly influence the optoelectronic properties of the QDs. In this article, we present a detailed review on atomic-scale characterization of droplet epitaxy quantum dots by cross-sectional scanning tunneling microscopy (X-STM) and atom probe tomography (APT). We will discuss both strain-free GaAs/AlGaAs QDs and strained InAs/InP QDs grown by droplet epitaxy. The effects of various growth conditions on morphology and composition are presented. The efficiency of methods such as flushing technique is shown by comparing with conventional droplet epitaxy QDs to further gain control over QD height. A detailed characterization of etch pits in both QD systems is provided by X-STM and APT. This review presents an overview of detailed structural and compositional analysis that have assisted in improving the fabrication of QD based optoelectronic devices grown by droplet epitaxy.
Download full-text PDF |
Source |
---|---|
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7823520 | PMC |
http://dx.doi.org/10.3390/nano11010085 | DOI Listing |
Nanomaterials (Basel)
November 2024
Faculty of Physics, St. Petersburg State University, Universitetskaya Emb. 13B, 199034 St. Petersburg, Russia.
This study investigates the growth of gallium arsenide nanowires, using lead as a catalyst. Typically, nanowires are grown through the vapor-solid-liquid mechanism, where a key factor is the reduction in the nucleation barrier beneath the catalyst droplet. Arsenic exhibits limited solubility in conventional catalysts; however, this research explores an alternative scenario in which lead serves as a solvent for arsenic, while gallium and lead are immiscible liquids.
View Article and Find Full Text PDFCryst Growth Des
November 2024
EPSRC National Epitaxy Facility, The University of Sheffield, North Campus, Broad Lane, Sheffield S3 7HQ, United Kingdom.
The local droplet etching (LDE) by using indium droplets on bare InP(100) surfaces is demonstrated in a metal-organic vapor phase epitaxy (MOVPE) environment for the first time. The role of an arsenic flow applied to self-assembled metallic indium droplets is systematically studied. Increasing the arsenic supply leads to the formation of ring-like nanostructures and nanoholes.
View Article and Find Full Text PDFNano Lett
August 2024
Institut für Festkörperphysik, Leibniz Universität Hannover, Appelstraße 2, 30167 Hannover, Germany.
Strain-free GaAs/AlGaAs semiconductor quantum dots (QDs) grown by droplet etching and nanohole infilling (DENI) are highly promising candidates for the on-demand generation of indistinguishable and entangled photon sources. The spectroscopic fingerprint and quantum optical properties of QDs are significantly influenced by their morphology. The effects of nanohole geometry and infilled material on the exciton binding energies and fine structure splitting are well-understood.
View Article and Find Full Text PDFNanotechnology
July 2024
Applied Physics and Science Education Department, Eindhoven University of Technology, 5600 MB, Eindhoven, The Netherlands.
Among the experimental realization of fault-tolerant topological circuits are interconnecting nanowires with minimal disorder. Out-of-plane indium antimonide (InSb) nanowire networks formed by merging are potential candidates. Yet, their growth requires a foreign material stem usually made of InP-InAs.
View Article and Find Full Text PDFMolecules
June 2024
Department of Physics, University of Warwick, Coventry CV4 7AL, UK.
InBi is a topological nodal line semimetal with strong spin-orbit coupling. It is epitaxially compatible with III-V semiconductors and, hence, an attractive material for topological spintronics. However, growth by molecular beam epitaxy (MBE) is challenging owing to the low melting point of InBi and the tendency to form droplets.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!