Download or read book Far Infrared Investigations of Electronic Intersubband Transitions in Seminconductor Multiple quantum well Structures written by Wei Jian Li and published by . This book was released on 1992 with total page 328 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Intersubband Transitions In Quantum Structures written by Roberto Paiella and published by McGraw Hill Professional. This book was released on 2010-05-05 with total page 454 pages. Available in PDF, EPUB and Kindle. Book excerpt: Advances in epitaxial growth and nanofabrication technology in the past several years have made it possible to engineer sophisticated semiconductor quantum devices with unprecedented control of their electronic and optical properties. A particularly important class of such devices is based on intersubband transitions, i.e. optical transitions between quantized electronic states in semiconductor heterostructures. Most notably, mid-infrared quantum-well infrared photodetectors (QWIPs) and quantum cascade lasers nowadays offer superior performance for applications such as thermal imaging, spectroscopy, and biochemical sensing, and have recently become commercially available. Intersubband devices also have the potential for a revolutionary impact in the fields of silicon photonics, terahertz sensing, and ultra-high-bandwidth fiber-optic communications, and extensive research is ongoing to fulfill this promise. Joined by an international group of world experts, Paiella describes the basic device physics and applications of intersubband transitions, as well as the more recent and important developments in this exciting area of semiconductor nanotechnology.
Download or read book Intersubband Transitions in Quantum Wells Physics and Devices written by Sheng S. Li and published by Springer. This book was released on 1998-07-31 with total page 232 pages. Available in PDF, EPUB and Kindle. Book excerpt: The purpose of Intersubband Transitions in Quantum Wells: Physics and Devices is to facilitate the presentation and discussion of the recent results in theoretical, experimental, and applied aspects of intersubband transitions in quantum wells and dots. This reference work is based on the International Workshop that was held at National Cheng Kung University in Tainan, Taiwan in December 15-18, 1997. Intersubband transitions in quantum wells and quantum dots have attracted considerable attention in recent years, mainly due to the promise of various applications in the mid- and far-infrared regions (2-30 mum). Over 40 invited and contributed papers were presented in this four-day workshop, with topics covering most aspects of the intersubband transition phenomena including: the basic intersubband transition process, multiquantum well infrared photodetector (QWIP) physics, large format (640×480) GaAs QWIP (with 9.0 mum cutoff) focal plane arrays (FPAs) for IR imaging camera applications, infrared modulation, intersubband emission including mid- and long-wavelength quantum cascade (QC) lasers such as short (lambda = 3.4 mum) and long (lambda = 11.5 mum) wavelength room temperature QC lasers, quantum fountain intersubband laser at 15.5 mum wavelength in GaAs/AIGaAs quantum well, harmonic generation and nonlinear effects, ultra-fast phenomena such as terahertz (THz) intersubband emission and detection. Intersubband Transitions in Quantum Wells: Physics and Devices will be of interest to researchers from universities and industrial laboratories working on physics and devices of nanostructures, and researchers in the infrared (IR) community.
Download or read book Intersubband Transitions in Quantum Wells written by Emmanuel Rosencher and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 341 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book contains the lectures delivered at the NATO Advanced Research Workshop on the "Intersubband Transistions in Quantum Wells" held in Cargese, France, between the t 9 h and the 14th of September 1991. The urge for this Workshop was justified by the impressive growth of work dealing with this subject during the last two or three years. Indeed, thanks to recent progresses of epitaxial growth techniques, such as Molecular Beam Epitaxy, it is now possible to realize semiconductor layers ( e.g. GaAs) with thicknesses controlled within one atomic layer, sandwiched between insulating layers (e.g. AlGaAs). When the semiconducting layer is very thin, i.e. less than 15 nm, the energy of the carriers corresponding to their motion perpendicular to these layers is quantized, forming subbands of allowed energies. Because of the low effective masses in these semiconducting materials, the oscillator strengths corresponding to intersubband transitions are extremely large and quantum optical effects become giant in the 5 - 20 ~ range: photoionization, optical nonlinearities, ... Moreover, a great theoretical surprise is that - thanks to the robustness of the effective mass theory - these quantum wells are a real life materialization of our old text book one-dimensional quantum well ideal. Complex physical phenomena may then be investigated on a simple model system.
Download or read book Asymmetric Quantum Well Structures for Enhanced Infrared Photon Absorption written by Mehjabeen Akhtar Khan and published by . This book was released on 2013 with total page 114 pages. Available in PDF, EPUB and Kindle. Book excerpt: Compared to inter-band transition for photon absorption in a quantum wells, intra-band (or inter-subband) transitions in heterojunction (GaAs/InP) quantum wells can provide access to a broader range of wavelengths for detector design, specifically detectors operating in the mid infrared region of spectrum (4-12 [micro]m) and beyond is possible. These quantum wells not only provide great flexibility in optimizing the Eigen energy levels or wavefunctions, and inter-subband optical matrix elements determining the corresponding transition probability, but also allow controlling electron-phonon scattering rates and thus electron lifetime. The research presented in this dissertation investigates asymmetric quantum well structures formed through III-V semiconductor material system such as AlGaAs/ InxGa(1-x)As/InyGa(1-y) As/AlGaAs that can further improve the responsivity through higher carrier mobility. Asymmetry is introduced by using multiple materials to form the well region. The advantage of exploring stepped quantum well structure stems from experimental evidence that such structures are capable of absorbing normal incidence and thus eliminates the requirement of incorporating additional optical coupling schemes such as grating structures. An important contribution of this research is the development of an analytical model to analyze single or multiple quantum well structures to quantify photon absorption. The physical model developed in this work is based on non-equilibrium Green's function (NEGF), Fermi's golden rule and quantum mechanical wave impedance concept. The approach has two distinct advantages. First, it is accurate, easily programmable and yet computationally efficient. Second, it facilitates quantifying the broadening of states resulting from both photon absorption and tunneling, which provides important insight for improving detection efficiency. Instead of being presented through calculations, such broadening has been simply assumed in previously reported works. The method developed in this research provides an efficient methodology to quantify the absorption rate of photons with different polarizations. The study looks into the design and analysis of the wells to enhance infrared radiation detection, and suggests mechanisms to optimize the structures in terms of material choice, composition, structural geometry and applied voltages. The high electron mobility and hence drift velocity in InGaAs ( >5×106cm/s), along with low carrier recapture lifetime, is expected to improve the detection speed of the device. Unlike GaAs/AlGaAs, the lattice mismatch at InGaAs/AlGaAs interface is likely to introduce strain in the structure. The effect of such strain as well as the layer thickness is taken into account in this work. Also, a methodology for achieving voltage tenability, i.e. the ability to detect different wavelengths at different bias voltages has been investigated. Although both n-type and p-type systems have potential for optoelectronic devices, n-type quantum wells are more advantageous because of their nearly parabolic sub-band structure. As for material consideration, direct band gap material based systems, such as AlGaAs/InGaAs and AlGaAs/GaAs, have been found to be particularly suitable for n-type QWIP photodetectors. The reason being that the electrons in such materials occupy states around the [gamma]valley where the effective mass is smaller and therefore mobility is higher; a condition which leads to higher photoresponsivity. Moreover such systems allow the possibility of highly stable device operation owing to the insensitivity of intra-band transition energies to temperature fluctuation and reduced influence of Auger recombination.
Download or read book Long Wavelength Infrared Emitters Based on Quantum Wells and Superlattices written by Manfred Helm and published by CRC Press. This book was released on 2000-10-31 with total page 424 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book offers a thorough survey of long wavelength infrared semiconductor emitters based primarily on quantum wells and superlattices. Featuring contributions from the most prominent researchers in the field, this volume allows readers to compare different types of lasers as well as examine investigations of potential far-infrared/terrahertz sources. This is an essential reference for researchers, engineers and graduate students who wish to obtain comprehensive knowledge about infrared semiconductor sources and recent developments in this field.
Download or read book Intersubband Transitions in Quantum Wells Physics and Devices written by Sheng S. Li and published by Springer Science & Business Media. This book was released on 2013-11-27 with total page 221 pages. Available in PDF, EPUB and Kindle. Book excerpt: The International Workshop on "Intersubband Transitions in Quantum Wells:: Physics and Applications," was held at National Cheng Kung University, in Tainan, Taiwan, December 15-18, 1997. The objective of the Workshop is to facilitate the presentation and discussion of the recent results in theoretical, experimental, and applied aspects of intersubband transitions in quantum wells and dots. The program followed the tradition initiated at the 1991 conference in Cargese-France, the 1993 conference in Whistler, B. C. Canada, and the 1995 conference in Kibbutz Ginosar, Israel. Intersubband transitions in quantum wells and quantum dots have attracted considerable attention in recent years, mainly due to the promise of various applications in the mid- and far-infrared regions (2-30 J. lm). Over 40 invited and contributed papers were presented in this four-day workshop, with topics covered most aspects of the intersubband transition phenomena including: the basic intersubband transition processes, multiquantum well infrared photodetector (QWIP) physics, large format (640x480) GaAs QWIP (with 9. 0 J. lffi cutoff) focal plane arrays (FPAs) for IR imaging camera applications, infrared modulation, intersubband emission including mid- and long- wavelength quantum cascade (QC) lasers such as short (A. "" 3. 4 J. lm) and long (A. "" 11. 5 J. lm) wavelength room temperature QC lasers, quantum fountain intersubband laser at 15. 5 J. lm wavelength in GaAs/AIGaAs quantum well, harmonic generation and nonlinear effects, ultra-fast phenomena such as terahertz (THz) intersubband emission and detection. The book divides into five Chapters.
Download or read book Optically detected resonances induced by far infrared radiation in quantum wells and quantum dots written by Michael Gerbracht and published by GRIN Verlag. This book was released on 2008-07-18 with total page 186 pages. Available in PDF, EPUB and Kindle. Book excerpt: Doctoral Thesis / Dissertation from the year 2008 in the subject Physics - Theoretical Physics, grade: 1,0, University of Dortmund (Experimentelle Physik II), language: English, abstract: Abstract Photoluminescence (PL) and optically detected resonances (ODR) where studied on semiconductor quantum wells and quantum dots. Magnetic fields of up to 33 T where applied to samples at temperatures between 0.25 K and 10 K. In nonmagnetic quantum wells optically detected cyclotron resonance was used to determine basic properties such as effective mass and mobility of GaAs/AlGaAs quantum wells. In CdTe/CdMgTe quantum wells evidence for the singlet and triplet state of the negatively and positively charged exciton was found at high magnetic fields. In a highly n-type doped GaAs/AlGaAs quantum well, signatures of the fractional quantum hall effect were observed in PL and ODR data. Also shake up processes in a variety of quantum wells are discussed. In magnetic quantum wells, cusps in the exciton shift are present at moderate magnetic fields which could be assigned to next nearest neighbor interactions between Mn2+ ion pairs and single ions. Resonances in InGaAs/GaAs quantum dots induced by far-infrared radiation have been observed optically. They were studied in quantum dots with different confinement potential and under a series of tilting angles between sample normal and magnetic field direction. The resonances could be assigned to trion formation due to cyclotron resonance in the wetting layer and transitions in the internal energy structure of the dots. Also magnetic CdMnTe/ZnCdTe quantum dots with different Mn content were measured at magnetic fields up to 17 T. At low Mn concentrations a competition between the giant and intrinsic Zeeman splitting leads to a reduction of the polarization of the sample at high magnetic field which makes it possible to determine the Mn content by photoluminescence measurements.
Download or read book Scientific and Technical Aerospace Reports written by and published by . This book was released on 1992 with total page 1556 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Dissertation Abstracts International written by and published by . This book was released on 2003 with total page 644 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Far Infrared Studies of Electron electron Interactions in Si Doped GaAs AlGaAs Multiple Quantum Wells written by Zhenxin Jiang and published by . This book was released on 1996 with total page 380 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Electron and Photon Confinement in Semiconductor Nanostructures written by Benoît Deveaud and published by IOS Press. This book was released on 2003 with total page 584 pages. Available in PDF, EPUB and Kindle. Book excerpt: The purpose of this course was to give an overview of the physics of artificial semiconductor structures confining electrons and photons. It furnishes the background for several applications in particular in the domain of optical devices, lasers, light emitting diodes or photonic crystals. The effects related to the microactivity polaritons, which are mixed electromagnetic radiation-exciton states inside a semiconconductor microactivity are covered. The study of the characteristics of such states shows strong relations with the domain of cavity quantum electrodynamics and thus with the investigation of some fundamental theoretical concepts.
Download or read book Long Wavelength Infrared Detectors written by Manijeh Razeghi and published by CRC Press. This book was released on 2020-03-09 with total page 393 pages. Available in PDF, EPUB and Kindle. Book excerpt: This timely work presents a comprehensive overview of the development of new generations of infrared detectors based on artificially synthesized quantum structures. The growth of quantum wells and superlattices is well documents in this volume, as are the principal new superlattice technologies for long wavelength infrared detection. Featuring insightful contributions from researchers working at the "cutting edge" of this exciting field, this volume is sure to become an essential reference for advanced graduate students and researchers alike.
Download or read book Spectroscopy of Semiconductor Microstructures written by Gerhard Fasol and published by Springer Science & Business Media. This book was released on 2013-06-29 with total page 661 pages. Available in PDF, EPUB and Kindle. Book excerpt: Proceedings of a NATO ARW held in Venice, Italy, May 9-13, 1989
Download or read book Intersubband Transitions in Quantum Wells written by H. C. Liu and published by . This book was released on 2000 with total page 332 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Terahertz Spectroscopy written by Susan L. Dexheimer and published by CRC Press. This book was released on 2017-12-19 with total page 358 pages. Available in PDF, EPUB and Kindle. Book excerpt: The development of new sources and methods in the terahertz spectral range has generated intense interest in terahertz spectroscopy and its application in an array of fields. Presenting state-of-the-art terahertz spectroscopic techniques, Terahertz Spectroscopy: Principles and Applications focuses on time-domain methods based on femtosecond laser sources and important recent applications in physics, materials science, chemistry, and biomedicine. The first section of the book examines instrumentation and methods for terahertz spectroscopy. It provides a comprehensive treatment of time-domain terahertz spectroscopic measurements, including methods for the generation and detection of terahertz radiation, methods for determining optical constants from time-domain measurements, and the use of femtosecond time-resolved techniques. The last two sections explore a variety of applications of terahertz spectroscopy in physics, materials science, chemistry, and biomedicine. With chapters contributed by leading experts in academia, industry, and research, this volume thoroughly discusses methods and applications, setting it apart from other recent books in this emerging terahertz field.
Download or read book Physics Briefs written by and published by . This book was released on 1994 with total page 1248 pages. Available in PDF, EPUB and Kindle. Book excerpt:
