Download or read book Characterization of Photo physical Properties of Semiconductor Quantum Dots at the Ensemble and Single Particle Level written by Florian Ekkehard Weigert and published by . This book was released on 2021 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Single Molecule Characterization of Photophysical and Colloidal Properties of Biocompatible Quantum Dots written by and published by . This book was released on 2003 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Colloidal semiconductor nanocrystals (NCs) have recently been introduced as novel fluorescent labels for various biological applications. Their unique optical properties -- tunable narrow emission spectrum, broad excitation spectrum, high photostability and long fluorescent lifetimes (on the order of tens of nanoseconds) -- make them attractive probes in experiments involving long observation times, multicolor and time-gated detection. Photophysical properties were investigated at the ensemble and single-molecule level for CdSe or CdTe core, CdSe/ZnS core-shell and surface-modified NCs. The use of NCs as fluorescent probes in biological applications requires various synthesis routes and surface modifications to enable solubility in aqueous solution and to allow labeling of biological macromolecules. Due to NC2s sensitivity to surface-defects chemical treatments have a significant influence on photophysical properties and need to be thoroughly monitored. Single-molecule fluorescence detection was used to characterize NC fluorescence, observe intermittency in the emission (blinking), and unravel a non-fluorescent subpopulation of NCs whose fluorescence can be restored through photo-induced activation. Stage-scanning confocal, epifluorescence and objective-type total-internal-reflection microscopy, were applied to observe surface-immobilized NCs. Fluorescence lifetimes were determined to be around 20 ns for single particles showing deviations from a mono-exponential decay. This observation was proven to be characteristic of single particles by monitoring photon antibunching. Fluorescence correlation spectroscopy (FCS) was used to characterize photophysical and colloidal properties in solution. It was shown to be a powerful technique to rapidly evaluate information on synthesis and surface modifications. These are essential to achieve water-solubility and bio-conjugation and dramatically influence the optical performance. FCS allows measuring concentration of fluorescent.
Download or read book Quantum Dots written by Lucjan Jacak and published by Springer Science & Business Media. This book was released on 2013-06-29 with total page 176 pages. Available in PDF, EPUB and Kindle. Book excerpt: We present an overview of the theoretical background and experimental re sults in the rapidly developing field of semiconductor quantum dots - systems 8 6 of dimensions as small as 10- -10- m (quasi-zero-dimensional) that contain a small and controllable number (1-1000) of electrons. The electronic structure of quantum dots, including the energy quan tization of the single-particle states (due to spatial confinement) and the evolution of these (Fock-Darwin) states in an increasing external magnetic field, is described. The properties of many-electron systems confined in a dot are also studied. This includes the separation of the center-of-mass mo tion for the parabolic confining potential (and hence the insensitivity of the transitions under far infrared radiation to the Coulomb interactions and the number of particles - the generalized Kohn theorem) and the effects due to Coulomb interactions (formation of the incompressible magic states at high magnetic fields and their relation to composite jermions), and finally the spin-orbit interactions. In addition, the excitonic properties of quantum dots are discussed, including the energy levels and the spectral function of a single exciton, the relaxation of confined carriers, the metastable states and their effect on the photoluminescence spectrum, the interaction of an exciton with carriers, and exciton condensation. The theoretical part of this work, which is based largely on original re sults obtained by the authors, has been supplemented with descriptions of various methods of creating quantum-dot structures.
Download or read book Single Molecule Characterization of Photophysical and Colloidal Properties of Biocompatible Quantum Dots written by Sören Doose and published by . This book was released on 2003 with total page 170 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Semiconductor Quantum Dots written by Y. Masumoto and published by Springer Science & Business Media. This book was released on 2013-04-17 with total page 500 pages. Available in PDF, EPUB and Kindle. Book excerpt: Semiconductor quantum dots represent one of the fields of solid state physics that have experienced the greatest progress in the last decade. Recent years have witnessed the discovery of many striking new aspects of the optical response and electronic transport phenomena. This book surveys this progress in the physics, optical spectroscopy and application-oriented research of semiconductor quantum dots. It focuses especially on excitons, multi-excitons, their dynamical relaxation behaviour and their interactions with the surroundings of a semiconductor quantum dot. Recent developments in fabrication techniques are reviewed and potential applications discussed. This book will serve not only as an introductory textbook for graduate students but also as a concise guide for active researchers.
Download or read book Semiconductor Quantum Dots written by Ladislaus Alexander Banyai and published by World Scientific. This book was released on 1993-05-28 with total page 264 pages. Available in PDF, EPUB and Kindle. Book excerpt: Semiconductor Quantum Dots presents an overview of the background and recent developments in the rapidly growing field of ultrasmall semiconductor microcrystallites, in which the carrier confinement is sufficiently strong to allow only quantized states of the electrons and holes. The main emphasis of this book is the theoretical analysis of the confinement induced modifications of the optical and electronic properties of quantum dots in comparison with extended materials. The book develops the theoretical background material for the analysis of carrier quantum-confinement effects, introduces the different confinement regimes for relative or center-of-mass motion quantization of the electron-hole-pairs, and gives an overview of the best approximation schemes for each regime. A detailed discussion of the carrier states in quantum dots is presented and surface polarization instabilities are analyzed, leading to the self-trapping of carriers near the surface of the dots. The influence of spin-orbit coupling on the quantum-confined carrier states is discussed. The linear and nonlinear optical properties of small and large quantum dots are studied in detail and the influence of the quantum-dot size distribution in many realistic samples is outlined. Phonons in quantum dots as well as the influence of external electric or magnetic fields are also discussed. Last but not least the recent developments dealing with regular systems of quantum dots are also reviewed. All things included, this is an important piece of work on semiconductor quantum dots not to be dismissed by serious researchers and physicists.
Download or read book Quantum Dots written by Michael Shur and published by World Scientific. This book was released on 2002 with total page 214 pages. Available in PDF, EPUB and Kindle. Book excerpt: In this book, leading experts on quantum dot theory and technology provide comprehensive reviews of all aspects of quantum dot systems. The following topics are covered: (1) energy states in quantum dots, including the effects of strain and many-body effects; (2) self-assembly and self-ordering of quantum dots in semiconductor systems; (3) growth, structures, and optical properties of III-nitride quantum dots; (4) quantum dot lasers.
Download or read book Fingerprints in the Optical and Transport Properties of Quantum Dots written by Ameenah Al-Ahmadi and published by BoD – Books on Demand. This book was released on 2012-06-13 with total page 482 pages. Available in PDF, EPUB and Kindle. Book excerpt: The book "Fingerprints in the optical and transport properties of quantum dots" provides novel and efficient methods for the calculation and investigating of the optical and transport properties of quantum dot systems. This book is divided into two sections. In section 1 includes ten chapters where novel optical properties are discussed. In section 2 involve eight chapters that investigate and model the most important effects of transport and electronics properties of quantum dot systems This is a collaborative book sharing and providing fundamental research such as the one conducted in Physics, Chemistry, Material Science, with a base text that could serve as a reference in research by presenting up-to-date research work on the field of quantum dot systems.
Download or read book Optical and Electrical Properties of Single Self Assembled Quantum Dots in Lateral Electric Fields written by Malte Huck and published by diplom.de. This book was released on 2010-03-25 with total page 137 pages. Available in PDF, EPUB and Kindle. Book excerpt: Inhaltsangabe:Abstract: Chapter 1: In this thesis we investigate the optical properties of self-assembled quantum dots exposed to a lateral electric field. As a result of the electric field the wave functions of electrons and holes inside the quantum dot are manipulated, which makes it possible to tune their energy levels and control the optical properties of the system. The possibility of tuning the emission energy of different few particle states using this method makes this system very promising for the use of a source of polarization entangled photons as discussed in the following sections. In Section 1.1 the concept of entangled states is introduced together with a brief historical overview. The possibility of using the exciton biexciton cascade of a self-assembled quantum dot for the generation of entangled photon pairs is presented in Section 1.2. Chapter 2: In this chapter we introduce the concept of quantum dots and demonstrate their optical emission properties. In Section 2.1 the quantum dot is introduced as a three-dimensional charge carrier trap. Several types of quantum dots are presented in an overview. In Section 2.2 we discuss the physical effects that occur on the way from bulk semiconductor material to the three-dimensional charge carrier confinement in the case of quantum dots. The growth of self-assembled quantum dot samples is the topic of Section 2.3, where the technique of molecular beam epitaxy is introduced (Section 2.3.1). This technique is used to grow the semiconductor quantum dots via heteroepitaxy in the Stranski-Krastanov growth mode (Section 2.3.2). Quantum dots are commonly referred to as artificial atoms due to their atomlike emission features. The origin for this expression is explained in Section 2.4 on the basis of the energetic structure of self-assembled quantum dots. The optical properties of quantum dots are discussed in Section 2.5, beginning with an introduction to the experimental setup that has been used to investigate the quantum dots during this thesis (Section 2.5.1). Different optical excitation modes are presented in Section 2.5.2 and in Section 2.5.3 we discuss, how to achieve a low enough quantum dot density on the analyzed samples. Section 2.5.4 deals with the photoluminescence of different exciton states and in Section 2.5.5 we present how these lines can be identified via power dependent measurements. Finally, the concept of initial charges in self-assembled quantum dots is presented in [...]
Download or read book Quantum Dots written by Orion Ciftja and published by . This book was released on 2012 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Nanoscience and nanotechnology is continuously moving forward enabling the precise, controlled fabrication of structures and devices at atomic and molecular scales. Quantum dots are typically semiconductor nanocrystals that have gained tremendous attention due to their unique electronic, magnetic, chemical and optical properties. They have proven very useful in applications in many fields across the physical, engineering, chemical, biological and medical sciences. In this book, the authors give an overview of the progress and major research developments in the field of quantum dots over the past two decades. They specifically focus on discussing the cutting-edge applications in the fields of information technology, electronics, biotechnology, energy, medicine, cellular imaging and diagnostic bio-sensing.
Download or read book Synthesis Characterization and Single Particle Spectroscopy of Semiconductor Quantum Dots and Quantum Dot Oligomers written by Nan Hu and published by . This book was released on 2015 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Quantum Dots written by Elena Borovitskaya and published by World Scientific. This book was released on 2002-07-08 with total page 214 pages. Available in PDF, EPUB and Kindle. Book excerpt: In this book, leading experts on quantum dot theory and technology provide comprehensive reviews of all aspects of quantum dot systems. The following topics are covered: (1) energy states in quantum dots, including the effects of strain and many-body effects; (2) self-assembly and self-ordering of quantum dots in semiconductor systems; (3) growth, structures, and optical properties of III-nitride quantum dots; (4) quantum dot lasers.
Download or read book Quantum Dots written by Inamuddin and published by Materials Research Forum LLC. This book was released on 2021-04-05 with total page 360 pages. Available in PDF, EPUB and Kindle. Book excerpt: The book provides a thorough survey of current research in quantum dots synthesis, properties, and applications. The unique properties of these new nanomaterials offer multifunctional applications in such fields as photovoltaics, light-emitting diodes, field-effect transistors, lasers, photodetectors, solar cells, biomedical diagnostics and quantum computing. Keywords: Quantum Dots (QD), Photovoltaics, Light-emitting Diodes, Field-effect Transistors, Lasers, Photodetectors, Solar Cells, Biomedical Diagnostics, Quantum Computing, QD Synthesis, Carbon QDs, Graphene QDs, QD Sensors, Supercapacitors, Magnetic Quantum Dots, Cellular/Molecular Separation, Chromatographic Separation Column, Photostability, Luminescence of Carbon QDs, QD Materials for Water Treatment, Semiconductor Quantum Dots, QD Drug Delivery, Antibacterial Quantum Dots.
Download or read book Tuning Semiconducting and Metallic Quantum Dots written by Christian von Borczyskowski and published by CRC Press. This book was released on 2017-03-27 with total page 407 pages. Available in PDF, EPUB and Kindle. Book excerpt: Nanotechnology is one of the growing areas of this century, also opening new horizons for tuning optical properties. This book introduces basic tuning schemes, including those on a single quantum object level, with an emphasis on surface and interface manipulation of semiconducting and metallic quantum dots. There are two opposing demands in current forefront applications of quantum dots as optical labels, namely high luminescence stability (suppression of luminescence intermittency) and controllable intermittency and bleaching on a single-particle level to facilitate super-resolution optical microscopy (for which Eric Betzig, Stefan W. Hell, and William E. Moerner were awarded the 2014 Nobel Prize in Chemistry). The book discusses these contradictory demands with respect to both an understanding of the basic processes and applications. The chapters are a combination of scholarly presentation and comprehensive review and include case studies from the authors’ research, including unpublished results. Special emphasis is on a detailed understanding of spectroscopic and dynamic properties of semiconducting quantum dots. The book is suitable for senior undergraduates and researchers in the fields of optical nanoscience, materials science, and nanotechnology.
Download or read book Quantum Dots written by Faten Divsar and published by BoD – Books on Demand. This book was released on 2020-06-24 with total page 94 pages. Available in PDF, EPUB and Kindle. Book excerpt: Quantum dots (QDs) are luminescent semiconductor nanocrystals with unique chemical and physical properties due to their size and highly compact structure. QDs were first proposed for use in luminescent concentrators to replace organic dye molecules. In this book, the interest is in taking advantage of the emission properties of QDS, which can be tuned by their size, resulting from quantum confinement. In addition, the book discusses the potential of QDs as contrast and therapeutic agents in the field of medicine.
Download or read book Single Semiconductor Quantum Dots written by Peter Michler and published by Springer Science & Business Media. This book was released on 2009-06-13 with total page 390 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book reviews recent advances in the field of semiconductor quantum dots via contributions from prominent researchers in the scientific community. Special focus is given to optical, quantum optical, and spin properties of single quantum dots.
Download or read book Quantum Dot Optoelectronic Devices written by Peng Yu and published by Springer Nature. This book was released on 2020-04-16 with total page 329 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book captures cutting-edge research in semiconductor quantum dot devices, discussing preparation methods and properties, and providing a comprehensive overview of their optoelectronic applications. Quantum dots (QDs), with particle sizes in the nanometer range, have unique electronic and optical properties. They have the potential to open an avenue for next-generation optoelectronic methods and devices, such as lasers, biomarker assays, field effect transistors, LEDs, photodetectors, and solar concentrators. By bringing together leaders in the various application areas, this book is both a comprehensive introduction to different kinds of QDs with unique physical properties as well as their preparation routes, and a platform for knowledge sharing and dissemination of the latest advances in a novel area of nanotechnology.
