[PDF] Defect Related Luminescence In Nanocrystals eBook

Author : Heidi Danielle Nelson
Publisher :
Page : 224 pages
File Size : 10,90 MB
Release : 2018
Category :
ISBN :

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Dopants and defects play an important role in the luminescence of semiconductors, from classic bulk phosphors to more recently developed colloidal nanocrystals. This thesis describes several studies on the photophysics of defect-related luminescence in semiconductor nanocrystals, with a particular focus on copper and silver charge-transfer luminescence. The combination of density functional theory (DFT) and spectroscopy can provide deeper insight into the photophysics of these materials and help resolve unanswered questions about their luminescence. In chapter 2, DFT is used to investigate various aspects of the electronic structure and photoluminescence mechanism of copper-doped CdSe nanocrystals, including the copper oxidation state, the origin of the broad luminescence line width, and the excited-state singlet−triplet splitting. These calculations support and expand upon previous experimental results. Chapter 3 extends these experimental and computational studies to silver-doped CdSe nanocrystals. These materials have very similar photoluminescence properties to their copper-doped analogues, but they have significant electronic-structure differences due to inverted bonding between the silver dopant and its neighboring anions. Chapter 4 addresses the similarities between the photoluminescence of copper-doped and copper indium sulfide nanocrystals. DFT calculations demonstrate a significant tendency for the hole to localize in the valence band of copper indium sulfide, which has significant copper character and resembles the copper impurity level in doped nanocrystals. Other dopants and defects can also influence nanocrystal luminescence in different ways. Chapter 5 addresses the effects of slow electron trapping and detrapping on the intensity and dynamics of delayed luminescence in nanocrystals by varying the excitation pulse width. Chapter 6 is an investigation of photoinduced magnetization in manganese-doped CdSe nanocrystals; the formation of excitonic magnetic polarons is studied by continuous-wave and time-resolved magneto-optical spectroscopies. Together, these studies demonstrate a variety of ways that dopants and defects can affect the photoluminescence of semiconductor nanocrystals.

Author : Tupei Chen
Publisher : CRC Press
Page : 732 pages
File Size : 37,64 MB
Release : 2016-10-14
Category : Technology & Engineering
ISBN : 1315357003

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Semiconductor nanocrystals and metal nanoparticles are the building blocks of the next generation of electronic, optoelectronic, and photonic devices. Covering this rapidly developing and interdisciplinary field, the book examines in detail the physical properties and device applications of semiconductor nanocrystals and metal nanoparticles. It begins with a review of the synthesis and characterization of various semiconductor nanocrystals and metal nanoparticles and goes on to discuss in detail their optical, light emission, and electrical properties. It then illustrates some exciting applications of nanoelectronic devices (memristors and single-electron devices) and optoelectronic devices (UV detectors, quantum dot lasers, and solar cells), as well as other applications (gas sensors and metallic nanopastes for power electronics packaging). Focuses on a new class of materials that exhibit fascinating physical properties and have many exciting device applications. Presents an overview of synthesis strategies and characterization techniques for various semiconductor nanocrystal and metal nanoparticles. Examines in detail the optical/optoelectronic properties, light emission properties, and electrical properties of semiconductor nanocrystals and metal nanoparticles. Reviews applications in nanoelectronic devices, optoelectronic devices, and photonic devices.

Author : Supakit Charnvanichborikarn
Publisher :
Page : 330 pages
File Size : 16,58 MB
Release : 2011
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ISBN :

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Research over the past decade has indicated that ion implantation provides an attractive way of forming nanocrystals in solids that exhibit some exciting new material properties. However, the size and size distribution of these nanoparticles are both very difficult parameters to control, especially when a subsequent thermal anneal is needed to form well-defined precipitates. This usually leads to somewhat uncontrolled growth by the Ostwald ripening effect. In addition, ion implantation is known to create structural damage to crystals (especially semiconductors such as silicon), which evolves into many types of defects depending on the annealing regime and degree of damage. Some of these defects in silicon are optically active and can be detected by photoluminescence (PL), while others are inactive and may act as non-radiative recombination centres.

Author : Lorenzo Pavesi
Publisher : John Wiley & Sons
Page : 648 pages
File Size : 37,48 MB
Release : 2010-02-02
Category : Technology & Engineering
ISBN : 9783527629961

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This unique collection of knowledge represents a comprehensive treatment of the fundamental and practical consequences of size reduction in silicon crystals. This clearly structured reference introduces readers to the optical, electrical and thermal properties of silicon nanocrystals that arise from their greatly reduced dimensions. It covers their synthesis and characterization from both chemical and physical viewpoints, including ion implantation, colloidal synthesis and vapor deposition methods. A major part of the text is devoted to applications in microelectronics as well as photonics and nanobiotechnology, making this of great interest to the high-tech industry.

Author : S. V. Gaponenko
Publisher : Cambridge University Press
Page : 263 pages
File Size : 39,1 MB
Release : 1998-10-28
Category : Science
ISBN : 0521582415

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Examines the optical properties of low-dimensional semiconductor structures, a hot research area - for graduate students and researchers.

Author : Victor I. Klimov
Publisher : CRC Press
Page : 584 pages
File Size : 40,27 MB
Release : 2017-12-19
Category : Technology & Engineering
ISBN : 1351834525

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A review of recent advancements in colloidal nanocrystals and quantum-confined nanostructures, Nanocrystal Quantum Dots is the second edition of Semiconductor and Metal Nanocrystals: Synthesis and Electronic and Optical Properties, originally published in 2003. This new title reflects the book’s altered focus on semiconductor nanocrystals. Gathering contributions from leading researchers, this book contains new chapters on carrier multiplication (generation of multiexcitons by single photons), doping of semiconductor nanocrystals, and applications of nanocrystals in biology. Other updates include: New insights regarding the underlying mechanisms supporting colloidal nanocrystal growth A revised general overview of multiexciton phenomena, including spectral and dynamical signatures of multiexcitons in transient absorption and photoluminescence Analysis of nanocrystal-specific features of multiexciton recombination A review of the status of new field of carrier multiplication Expanded coverage of theory, covering the regime of high-charge densities New results on quantum dots of lead chalcogenides, with a focus studies of carrier multiplication and the latest results regarding Schottky junction solar cells Presents useful examples to illustrate applications of nanocrystals in biological labeling, imaging, and diagnostics The book also includes a review of recent progress made in biological applications of colloidal nanocrystals, as well as a comparative analysis of the advantages and limitations of techniques for preparing biocompatible quantum dots. The authors summarize the latest developments in the synthesis and understanding of magnetically doped semiconductor nanocrystals, and they present a detailed discussion of issues related to the synthesis, magneto-optics, and photoluminescence of doped colloidal nanocrystals as well. A valuable addition to the pantheon of literature in the field of nanoscience, this book presents pioneering research from experts whose work has led to the numerous advances of the past several years.

Author : Hardev Singh Virk
Publisher : Trans Tech Publications Ltd
Page : 260 pages
File Size : 27,69 MB
Release : 2014-07-18
Category : Technology & Engineering
ISBN : 3038265780

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The word luminescence was first used by a German physicist, Eilhardt Wiedemann, in 1888. He also classified luminescence into six kinds according to the method of excitation. No better basis of classification is available today. He recognized photoluminescence, thermoluminescence, electroluminescence, crystalloluminescence, triboluminescence, and chemiluminescence. The designations are obvious, characterized by the prefix. This Volume consists of 9 Chapters, including 8 Review Papers and one Case Study. The first two papers are based on OLEDs. Organic light emitting diodes (OLEDs) have been the focus of intense study since the late 1980s. Since that time, research has continued to demonstrate the potential of OLEDs as viable systems for displays and eco-friendly lighting applications. Thejokalyani and Sanjay Dhoble have given historical introduction to OLEDs in the first chapter under the title “Importance of Eco-friendly OLED Lighting”. They describe core fabrication technologies and applications of OLEDs in their paper. V. K. Chandra et al. have covered both theoretical and experimental aspects in their paper, “Organic Light - Emitting Diodes and their Applications” in the most rigorous way. This Chapter describes the salient features of OLEDs and discusses the applications of OLEDs in displays and solid state lighting devices.Organic-inorganic hybrid nanocomposite materials have been of great interest for their extraordinary performances. Interaction between the polymer matrix and nanocrystalline fillers produces wonderful features, viz. thermal, magnetic, mechanical, electrical and optical properties to these materials. S.K. Tripathi et al. have reviewed the present status of II-VI polymer nanocomposites from the photoluminescence studies point of view in the 3rd Chapter. Electroluminescence in undoped and doped chalcogenide nanocrystals and nanocomposites is reviewed in 4th Chapter by Meera et al. Nanocrystalline powder samples of CdS, CdSe, ZnS and ZnSe nanocrystals and their composites with PVA and PVK have been prepared by chemical route and investigated in detail. Chapters 5 and 6 are contributed by RK Gartia on two important topics: “Thermoluminescence of Persistent Luminescent Materials” and “Design of Inorganic Scintillators: Role of Thermoluminescence”. The author has demonstrated the application of TL, by virtue of its inherent sensitivity coupled with its universal applicability, to investigate practically all semiconducting/inorganic materials in terms of their trap- spectroscopy.Chapter 7 by Rabiul Biswas deals with application of luminescence to earth and planetary sciences. The author discusses some landmarks and recent developments in this field of luminescence dating with stress on extending the dating range. Chapter 8 by Jain and Bøtter-Jensen is focused on the developments around the Risø-TL/OSL reader which is popular amongst the dating community. The 9th Chapter is added as a case study. The authors, JN Reddy and KVR Murthy, claim that the primary objective of their PC Controlled TL Reader is to bring out versatile TL instrumentation system and also to make it affordable to many of the researchers in the Universities and other areas, including Radio-therapy and Medical Physics.

Author : Sergio Pizzini
Publisher : CRC Press
Page : 295 pages
File Size : 49,12 MB
Release : 2020-05-11
Category : Technology & Engineering
ISBN : 1000066134

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Defects in Nanocrystals: Structural and Physico-Chemical Aspects discusses the nature of semiconductor systems and the effect of the size and shape on their thermodynamic and optoelectronic properties at the mesoscopic and nanoscopic levels. The nanostructures considered in this book are individual nanometric crystallites, nanocrystalline films, and nanowires of which the thermodynamic, structural, and optical properties are discussed in detail. The work: Outlines the influence of growth processes on their morphology and structure Describes the benefits of optical spectroscopies in the understanding of the role and nature of defects in nanostructured semiconductors Considers the limits of nanothermodynamics Details the critical role of interfaces in nanostructural behavior Covers the importance of embedding media in the physico-chemical properties of nanostructured semiconductors Explains the negligible role of core point defects vs. surface and interface defects Written for researchers, engineers, and those working in the physical and physicochemical sciences, this work comprehensively details the chemical, structural, and optical properties of semiconductor nanostructures for the development of more powerful and efficient devices.

Author : Bernard Pichaud
Publisher : Trans Tech Publications Ltd
Page : 830 pages
File Size : 47,17 MB
Release : 2005-12-15
Category : Technology & Engineering
ISBN : 303813029X

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Volume is indexed by Thomson Reuters CPCI-S (WoS). This proceedings volume contains 126 contributions from the 11th international meeting on Gettering and Defect Engineering in Semiconductor Technology GADEST 2005 held at “La Badine” at the Giens peninsula south of France.

Author : Writam Banerjee
Publisher : CRC Press
Page : 683 pages
File Size : 45,15 MB
Release : 2024-08-09
Category : Technology & Engineering
ISBN : 1040119107

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In recent years, the abundant advantages of quantum physics, quantum dots, quantum wires, quantum wells, and nanocrystals in various applications have attracted considerable scientific attention in the field of nonvolatile memory (NVM). Nanocrystals are the driving elements that have helped nonvolatile flash memory technology reach its distinguished height, but new approaches are still needed to strengthen nanocrystal-based nonvolatile technology for future applications. This book presents comprehensive knowledge on nanocrystal fabrication methods and applications of nanocrystals in baseline NVM and emerging NVM technologies and the chapters are written by experts in the field from all over the globe. The book presents a detailed analysis on nanocrystal-based emerging devices by a high-level researcher in the field. It has a unique chapter especially dedicated to graphene-based flash memory devices, considering the importance of carbon allotropes in future applications. This updated edition covers emerging ferroelectric memory device, which is a technology for the future, and the chapter is contributed by the well-known Ferroelectric Memory Company, Germany. It includes information related to the applications of emerging memories in sensors and the chapter is contributed by Ajou University, South Korea. The book introduces a new chapter for emerging NVM technology in artificial intelligence and the chapter is contributed by University College London, UK. It guides the readers throughout with appropriate illustrations, excellent figures, and references in each chapter. It is a valuable tool for researchers and developers from the fields of electronics, semiconductors, nanotechnology, materials science, and solid-state memories.