Download or read book Quantum Dot Long Wavelength Detectors written by Pallab Bhattacharya and published by . This book was released on 2002 with total page 8 pages. Available in PDF, EPUB and Kindle. Book excerpt: Long-wavelength infrared detectors operating at elevated temperatures are critical for imaging applications. InAs/GaAs quantum dots are an important material for the design and fabrication of high-temperature infrared photodetectors. Quantum dot infrared photodetectors allow normal-incidence operation, in addition to low dark currents and multispectral response. The long intersubband relaxation time of electrons in quantum dots improves the responsivity of the detectors, contributing to better high-temperature performance. We have obtained extremely low dark currents (I(sub dark) = 1.7 pA, T = 100 K, V(sub bias) 0.1 V), high detectivities (D* = 2.9 x 10(exp 8) cm Hz(sup 1/2)/W, T = 100 K, V(sub bias) = 0.2 V), and high operating temperatures (T 150 K) for these quantum-dot detectors. These results, as well as infrared imaging with QDIPs. will be described and discussed.
Download or read book Quantum Dot Intersubband Long Wavelength Detector Arrays written by and published by . This book was released on 2004 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: In(Ga, Al)As/(Ga, Al)As QDIPs are positioned to become an important technology in the field of IR detection, particularly for the type of high-temperature, low-cost, high-yield detector arrays required for the military and other highly sophisticated applications. This research has advanced the state-of-the-art in QDIP performance, demonstrating that it is reasonable to incorporate these devices into a FPA operating at 150 K for MWIR detection. For example, at this temperature of operation, J(sub dark) 10(exp -5) A/sq cm, R(sub peak) 0.2 - 0.3 A/W and D ̂10 (exp 10) cm. Hz(exp 1/2/W. These improvements have been achieved by investigating several significant areas of QDIP operation to obtain a complete picture of the many different factors that affect detector performance: i) MBE growth of QDs for increased absorption of IR light, ii) design, fabrication, and characterization of state-of-the-art, discrete QDIPs operating at elevated temperatures, and iii) the characterization of small QDIP array properties.
Download or read book Proceedings of the Sixth International Symposium on Long Wavelength Infrared Detectors and Arrays Physics and Applications written by Sheng S. Li and published by The Electrochemical Society. This book was released on 1999 with total page 258 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Proceedings of the Fifth International Symposium on Long Wavelength Infrared Detectors and Arrays Physics and Applications written by Sheng S. Li and published by The Electrochemical Society. This book was released on 1997 with total page 296 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Quantum Dot Photodetectors written by Xin Tong and published by Springer Nature. This book was released on 2021-09-17 with total page 319 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book presents a comprehensive overview of state-of-the-art quantum dot photodetectors, including device fabrication technologies, optical engineering/manipulation strategies, and emerging photodetectors with building blocks of novel quantum dots (e.g. perovskite) as well as their hybrid structured (e.g. 0D/2D) materials. Semiconductor quantum dots have attracted much attention due to their unique quantum confinement effect, which allows for the facile tuning of optical properties that are promising for next-generation optoelectronic applications. Among these remarkable properties are large absorption coefficient, high photosensitivity, and tunable optical spectrum from ultraviolet/visible to infrared region, all of which are very attractive and favorable for photodetection applications. The book covers both fundamental and frontier research in order to stimulate readers' interests in developing novel ideas for semiconductor photodetectors at the center of future developments in materials science, nanofabrication technology and device commercialization. The book provides a knowledge sharing platform and can be used as a reference for researchers working in the fields of photonics, materials science, and nanodevices.
Download or read book Long Wavelength Quantum Dot Intersubband Optoelectronic Devices written by and published by . This book was released on 2001 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: While interband transitions in quantum dots have been extensively investigated for long wavelength (1.3 and 1.55 micrometers) optical communications, intersubband transitions between the electronic levels formed in the conduction band of the quantum dot have not been widely researched. Since the intersubband energy spacing lies in the mid-infrared (3-20 micrometers) range, these transitions can be used for fabricating mid-infrared sources and detectors, which are in great need for applications such as space based infrared imaging, thermal imaging, night vision, thermography for electrical and mechanical fault detection, FTIR spectroscopy and environmental and chemical process monitoring. In this project, intersubband transitions in self-organized In(Ga)As/OaAs quantum dots were investigated and mid-infrared sources and detectors were fabricated. Spontaneous and stimulated emission centered at 13 micrometers, was observed for the first time. We have also fabricated normal incidence quantum dot detectors with very low dark current, high detectivity, and peak responsivity with a photoconductive gain with the highest operating temperature (150K) for any normal incidence vertical quantum dot detector.
Download or read book Quaternary Capped In Ga As GaAs Quantum Dot Infrared Photodetectors written by Sourav Adhikary and published by Springer. This book was released on 2017-09-06 with total page 72 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book introduces some alternative methods for enhancing the performance of In(Ga)As/GaAs-based quantum dot infrared photodetectors (QDIPs). In(Ga)As/GaAs-based QDIPs and focal plane array (FPA) cameras have wide application in fields such as military and space science. The core of the study uses a combination of quaternary In0.21Al0.21Ga0.58As and GaAs spacer as a capping layer on In(Ga)As/GaAs quantum dots in the active region of the detector structure. For the purposes of optimization, three types of samples growths are considered with different capping thicknesses. The results presented include TEM, XRD and photoluminescence studies that compare combination barrier thickness and its effect on structural and optical properties. Compressive strain within the heterostructure, thermal stability in high temperature annealing, spectral response, shifts in PL peaks peak,and responsivity and detectivity are all considered. The results also present a narrow spectral width that was obtained by using InAs QDs which is very useful for third generation FPA camera application. The book details effect of post-growth rapid thermal annealing on device characteristics and methods to enhance responsivity and peak detectivity. The contents of this book will be useful to researchers and professionals alike.
Download or read book Quantum Dot Sensors written by John Callan and published by CRC Press. This book was released on 2013-01-24 with total page 232 pages. Available in PDF, EPUB and Kindle. Book excerpt: Consisting of six chapters, written by experts in their field, this book charts the progress made in the use of quantum dots as the signaling component in optical sensors since their discovery in the early 1980s. In particular, it focuses on CdS-, CdSe-, and CdTe-type QDs due to their emission in the visible region of the electromagnetic spectrum. The book begins by detailing the range of methods currently used for the preparation and passivation of core/core–shell quantum dots and follows with a discussion on their electrochemical properties and potential toxicity. The book culminates by focusing on how electron and energy transfer mechanisms can be utilized to generate a range of quantum dot-based probes. This is the first text of its kind dedicated to quantum dot-based sensors and will appeal to those readers who have an interest in working with these versatile nanoparticles.
Download or read book Quantum Dot Devices written by Zhiming M. Wang and published by Springer Science & Business Media. This book was released on 2012-05-24 with total page 375 pages. Available in PDF, EPUB and Kindle. Book excerpt: Quantum dots as nanomaterials have been extensively investigated in the past several decades from growth to characterization to applications. As the basis of future developments in the field, this book collects a series of state-of-the-art chapters on the current status of quantum dot devices and how these devices take advantage of quantum features. Written by 56 leading experts from 14 countries, the chapters cover numerous quantum dot applications, including lasers, LEDs, detectors, amplifiers, switches, transistors, and solar cells. Quantum Dot Devices is appropriate for researchers of all levels of experience with an interest in epitaxial and/or colloidal quantum dots. It provides the beginner with the necessary overview of this exciting field and those more experienced with a comprehensive reference source.
Download or read book Structural Optical and Spectral Behaviour of InAs based Quantum Dot Heterostructures written by Saumya Sengupta and published by Springer. This book was released on 2017-08-04 with total page 77 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book explores the effects of growth pause or ripening time on the properties of quantum dots(QDs). It covers the effects of post-growth rapid thermal annealing (RTA) treatment on properties of single layer QDs. The effects of post-growth rapid thermal annealing (RTA) treatment on properties of single layer QDs are discussed. The book offers insight into InAs/GaAs bilayer QD heterostructures with very thin spacer layers and discusses minimum spacer thickness required to grow electronically coupled bilayer QD heterostructures. These techniques make bilayer QD heterostructures a better choice over the single layer and uncoupled multilayer QD heterostructure. Finally, the book discusses sub-monolayer (SML) growth technique to grow QDs. This recent technique has been proven to improve the device performance significantly. The contents of this monograph will prove useful to researchers and professionals alike.
Download or read book Stress Engineered Quantum Dots for Multispectral Infra Red Detector Arrays written by and published by . This book was released on 2006 with total page 9 pages. Available in PDF, EPUB and Kindle. Book excerpt: During the above-noted period of this Final Technical Report, the following salient milestones were reached: (1) Introduced and demonstrated the concept of injecting electrons into the quantum dot (OD) active infra-red absorbing region from bracketing doped contact layers (to suppress unwanted dark current) leaving the QD region undoped; (2) Introduced and demonstrated the benefits of the concepts of (a) strain-relieving OD capping layers, (b) current blocking layers, and (c) lateral potential confinement layer for tailoring the OD electronic response to the desired IR response; (3) Demonstrated high performance ODIP devices in the mid and longwavelength IR regions; (4) Demonstrated voltage-tunable mid and long IR dual wavelength ODIPs.
Download or read book Final LDRD Report written by and published by . This book was released on 2008 with total page 43 pages. Available in PDF, EPUB and Kindle. Book excerpt: Alternative solutions are desired for mid-wavelength and long-wavelength infrared radiation detection and imaging arrays. We have investigated quantum dot infrared photodetectors (QDIPs) as a possible solution for long-wavelength infrared (8 to 12 [mu]m) radiation sensing. This document provides a summary for work done under the LDRD 'Infrared Detection and Power Generation Using Self-Assembled Quantum Dots'. Under this LDRD, we have developed QDIP sensors and made efforts to improve these devices. While the sensors fabricated show good responsivity at 80 K, their detectivity is limited by high noise current. Following efforts concentrated on how to reduce or eliminate this problem, but with no clear path was identified to the desired performance improvements.
Download or read book Infrared and Terahertz Detectors Third Edition written by Antoni Rogalski and published by CRC Press. This book was released on 2019-01-10 with total page 1044 pages. Available in PDF, EPUB and Kindle. Book excerpt: This new edition of Infrared and Terahertz Detectors provides a comprehensive overview of infrared and terahertz detector technology, from fundamental science to materials and fabrication techniques. It contains a complete overhaul of the contents including several new chapters and a new section on terahertz detectors and systems. It includes a new tutorial introduction to technical aspects that are fundamental for basic understanding. The other dedicated sections focus on thermal detectors, photon detectors, and focal plane arrays.
Download or read book Intersubband Infrared Photodetectors written by Victor Ryzhii and published by World Scientific. This book was released on 2003-06-25 with total page 359 pages. Available in PDF, EPUB and Kindle. Book excerpt: Infrared technologies are very important for a wide range of military, scientific and commercial applications. Devices and systems based on semiconductor heterostructure and quantum well and quantum dot structures open up a new era in infrared technologies.This book deals with various topics related to the latest achievements in the development of intersubband infrared photodetectors, reviewed by top experts in the field. It covers physical aspects of the operation of the devices as well as details of their design in different applications. The papers included in the book will be useful for researchers and engineers interested in the physics of optoelectronic devices as well as their practical design and applications.
Download or read book Detection of Optical Signals written by Antoni Rogalski and published by CRC Press. This book was released on 2022-06-09 with total page 551 pages. Available in PDF, EPUB and Kindle. Book excerpt: Detection of Optical Signals provides a comprehensive overview of important technologies for photon detection, from the X-ray through ultraviolet, visible, infrared to far-infrared spectral regions. It uniquely combines perspectives from many disciplines, particularly within physics and electronics, which are necessary to have a complete understanding of optical receivers. This interdisciplinary textbook aims to: Guide readers into more detailed and technical treatments of readout optical signals Give a broad overview of optical signal detection including terahertz region and two-dimensional material Help readers further their studies by offering chapter-end problems and recommended reading. This is an invaluable resource for graduate students in physics and engineering, as well as a helpful refresher for those already working with aerospace sensors and systems, remote sensing, thermal imaging, military imaging, optical telecommunications, infrared spectroscopy, and light detection.
Download or read book Tunnel Quantum Dot Intersubband Detector for Terahertz Frequencies written by and published by . This book was released on 2009 with total page 13 pages. Available in PDF, EPUB and Kindle. Book excerpt: The most significant accomplishments in this project are: (a) the demonstration of a semiconductor based terahertz detector using quantum dots, capable of detection at high temperatures (80-150K) with very low dark currents: (b) a bias-selective multicolor long wavelength quantum dot intersublevel detector with tunability over 3 distinct wavelengths. The detector incorporates a novel double barrier tunneling heterostructure with each absorbing quantum dot layer; (c) a novel intersubband quantum ring terahertz detector with a resonant tunneling filter to reduce the dark current, which is the lowest ever measured. This device demonstrates terahertz detection with 0.4A/W in the 3-6THz range and detection in the 10-11 ThZ range at 120K.
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.
