Download or read book Controlled Growth of InAs GaAs Sel assembled Quantum Dots written by and published by . This book was released on 2002 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Controlled Growth of InAs GaAs Self assembled Quantum Dots written by Peter Brian Joyce and published by . This book was released on 2002 with total page 310 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Self Assembled Quantum Dots written by Zhiming M Wang and published by Springer Science & Business Media. This book was released on 2007-11-29 with total page 470 pages. Available in PDF, EPUB and Kindle. Book excerpt: This multidisciplinary book provides up-to-date coverage of carrier and spin dynamics and energy transfer and structural interaction among nanostructures. Coverage also includes current device applications such as quantum dot lasers and detectors, as well as future applications to quantum information processing. The book will serve as a reference for anyone working with or planning to work with quantum dots.
Download or read book Mechanisms Governing the Growth of Self assembled Quantum Dots written by Bruno J. Riel and published by . This book was released on 2002 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: We produced self-assembled quantum dot (QD) samples of InAs on GaAs by molecular beam epitaxy (MBE). With these, we explored growth effects as a function of InAs coverage for three arsenic pressures, and as a function of arsenic pressure at a specific InAs coverage. During growth, the samples were studied using reflection high energy electron diffraction (RHEED). These RHEED measurements were compared to low energy electron diffraction (LEED) measurements. To perform this ex-situ LEED characterisation, some samples were covered with an amorphous arsenic cap. This cap was thermally evaporated producing a clean, non-oxidised surface that was studied using LEED. We obtained non-ambiguous identification of the GaAs (001) surface reconstructions as well as timing information for the 2D to 3D transition during the growth of InAs on GaAs. Post growth characterisation of two sets of self-assembled QD samples, twelve samples in all, revealed the following: As a function of increasing the arsenic pressure used in QD growth, the photoluminescence (PL) of capped QDs is first redshifted at low arsenic pressures, and then blueshifted at high arsenic pressures. Scanning electron microscopy and atomic force microscopy of uncapped QDs show that as the arsenic pressure increases, the QD density increases while the average QD width and height decrease monotonically; these trends are consistent with the shift in PL for the high arsenic pressure samples, but are inconsistent with the shift in PL for the low pressure samples. This leads us to proposing a mechanism by which QDs may be modified as they are overgrown with capping material. We discuss the effects of adjusting the arsenic pressure on the formation of QDs and the mechanism by which QDs may be modified during capping.
Download or read book Self Assembled InGaAs GaAs Quantum Dots written by and published by Academic Press. This book was released on 1999-03-29 with total page 385 pages. Available in PDF, EPUB and Kindle. Book excerpt: This volume is concerned with the crystal growth, optical properties, and optical device application of the self-formed quantum dot, which is one of the major current subjects in the semiconductor research field.The atom-like density of states in quantum dots is expected to drastically improve semiconductor laser performance, and to develop new optical devices. However, since the first theoretical prediction for its great possibilities was presented in 1982, due to the difficulty of their fabrication process. Recently, the advent of self-organized quantum dots has made it possible to apply the results in important optical devices, and further progress is expected in the near future.The authors, working for Fujitsu Laboratories, are leading this quantum-dot research field. In this volume, they describe the state of the art in the entire field, with particular emphasis on practical applications.
Download or read book Impact of Ion Implantation on Quantum Dot Heterostructures and Devices written by Arjun Mandal and published by Springer. This book was released on 2017-06-02 with total page 84 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book looks at the effects of ion implantation as an effective post-growth technique to improve the material properties, and ultimately, the device performance of In(Ga)As/GaAs quantum dot (QD) heterostructures. Over the past two decades, In(Ga)As/GaAs-based QD heterostructures have marked their superiority, particularly for application in lasers and photodetectors. Several in-situ and ex-situ techniques that improve material quality and device performance have already been reported. These techniques are necessary to maintain dot density and dot size uniformity in QD heterostructures and also to improve the material quality of heterostructures by removing defects from the system. While rapid thermal annealing, pulsed laser annealing and the hydrogen passivation technique have been popular as post-growth methods, ion implantation had not been explored largely as a post-growth method for improving the material properties of In(Ga)As/GaAs QD heterostructures. This work attempts to remedy this gap in the literature. The work also looks at introduction of a capping layer of quaternary alloy InAlGaAs over these In(Ga)As/GaAs QDs to achieve better QD characteristics. The contents of this volume will prove useful to researchers and professionals involved in the study of QDs and QD-based devices.
Download or read book Homogeneity Improvement of InAs GaAs Self assembled Quantum Dots Grown by Molecular Beam Epitaxy written by Suwit Kiravittaya and published by . This book was released on 2002 with total page 186 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Growth Simulations of InAs GaAs Quantum Dots written by Thomas Hammerschmidt and published by . This book was released on 2006 with total page 161 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Verzameling propagandamateriaal voor de parlementsverkiezingen in Indonesi april 2009 written by and published by . This book was released on 2009 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Self assembled In Al Ga As Ga Al As Quantum Dots for Intersubband Detectors written by Jamie Dean Phillips and published by . This book was released on 1998 with total page 410 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Epitaxial Growth of Spatially and Spectrally Controlled Quantum Dots and Quantum Dot Molecules written by Lauren Nowicki McCabe and published by . This book was released on 2022 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Epitaxially grown InAs quantum dots (QDs) have long been researched as a promising basis for qubits, and there have been numerous quantum operations proof-of-concept studies performed. However, the random nucleation of these QDs as well as inhomogeneity in their composition, size, and shape has made it difficult to fabricate arrays of these nanostructures for scalable device integration. Other quantum device technologies also suffer from these same types of materials issues. In this research, a molecular beam epitaxy (MBE) grown materials platform for site-controlled InAs QDs in combination with quantum dot molecules (QDMs) for built in spectral tunability is introduced.
Download or read book Growth Control Structural Characterization and Electronic Structure of Stranski Krastanow InAs GaAs 001 Quantum Dots written by Ildar Mukhametzhanov and published by . This book was released on 2002 with total page 512 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Mme la comtesse Dash Cisterne de Courtras vicomtesse de Saint Mars written by and published by . This book was released on 1866 with total page 2 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Study of the Formation Mechanism of Self Assembled Quantum Dot Arrays with a Focus on Alloying and Nucleation Control written by and published by . This book was released on 2004 with total page 35 pages. Available in PDF, EPUB and Kindle. Book excerpt: The objective of the research project is to further the understanding of key materials science with regard to the formation mechanism of semiconductor self assembled quantum dots via epitaxy. During the funding period of 3+ years, we have made significant progress in that direction. We have conducted in-depth study on the following specific topics: the importance of alloying during epitaxial growth of SAQDs; the function of buried misfit dislocation in guided self-assembly by epitaxy; key issues pertinent to the growth of III-V on Si(001); and finally, the feasibility of fabricating quantum dot lasers of InAs or GaAs on Si. The importance of alloying was studied using the combination of Ge SAQD on Si in which the critical dot size for pyramid-to-dome transition was shown to increase significantly with increasing intermixing between Ge and Si. Using a buried misfit dislocation network, we have been able to demonstrate three distinctively different types of nucleation sites on Si(001). Furthermore, a properly designed, partially relaxed SiGe buffer layer has been shown to be a valuable vehicle for studying the formation mechanism of Ge SAQDs on Si. One of the applications was to experimentally determine the diffusion constant of Ge on Si and on Sb covered Si. We have also shown that the growth of III-V on Si is via Vomer-Weber mode without a wetting layer. Furthermore, the critical dot size for dislocation of InAs SAQDs on Si is less than 5 nm, making it a fundamental hurdle for fabricating lasers on Si.
Download or read book Growth of In Ga As GaAs Self organized Quantum Dots and Their Application to High speed Lasers and Spin polarized Light Sources written by Siddhārtha Ghosha and published by . This book was released on 2003 with total page 350 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Lateral Alignment of Epitaxial Quantum Dots written by Oliver G. Schmidt and published by Springer Science & Business Media. This book was released on 2007-08-17 with total page 700 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book describes the full range of possible strategies for laterally aligning self-assembled quantum dots on a substrate surface, beginning with pure self-ordering mechanisms and culminating with forced alignment by lithographic positioning. The text addresses both short- and long-range ordering phenomena and introduces future high integration of single quantum dot devices on a single chip. Contributions by well-known experts ensure that all relevant quantum-dot heterostructures are elucidated from diverse perspectives.
Download or read book Self Assembled InGaAs GaAs Quantum Dots written by and published by Academic Press. This book was released on 1999-04-05 with total page 368 pages. Available in PDF, EPUB and Kindle. Book excerpt: This volume is concerned with the crystal growth, optical properties, and optical device application of the self-formed quantum dot, which is one of the major current subjects in the semiconductor research field. The atom-like density of states in quantum dots is expected to drastically improve semiconductor laser performance, and to develop new optical devices. However, since the first theoretical prediction for its great possibilities was presented in 1982, due to the difficulty of their fabrication process. Recently, the advent of self-organized quantum dots has made it possible to apply the results in important optical devices, and further progress is expected in the near future. The authors, working for Fujitsu Laboratories, are leading this quantum-dot research field. In this volume, they describe the state of the art in the entire field, with particular emphasis on practical applications.
