Download or read book Exciton phonon Coupling in Monolayers of Transition Metal Dichalcogenides written by Malte Selig and published by . This book was released on 2018 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Atom Photon Interactions written by Claude Cohen-Tannoudji and published by John Wiley & Sons. This book was released on 1998-03-23 with total page 691 pages. Available in PDF, EPUB and Kindle. Book excerpt: Atom-Photon Interactions: Basic Processes and Applications allows the reader to master various aspects of the physics of the interaction between light and matter. It is devoted to the study of the interactions between photons and atoms in atomic and molecular physics, quantum optics, and laser physics. The elementary processes in which photons are emitted, absorbed, scattered, or exchanged between atoms are treated in detail and described using diagrammatic representation. The book presents different theoretical approaches, including: Perturbative methods The resolvent method Use of the master equation The Langevin equation The optical Bloch equations The dressed-atom approach Each method is presented in a self-contained manner so that it may be studied independently. Many applications of these approaches to simple and important physical phenomena are given to illustrate the potential and limitations of each method.
Download or read book Two Dimensional Transition Metal Dichalcogenides written by Alexander V. Kolobov and published by Springer. This book was released on 2016-07-26 with total page 545 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book summarizes the current status of theoretical and experimental progress in 2 dimensional graphene-like monolayers and few-layers of transition metal dichalcogenides (TMDCs). Semiconducting monolayer TMDCs, due to the presence of a direct gap, significantly extend the potential of low-dimensional nanomaterials for applications in nanoelectronics and nano-optoelectronics as well as flexible nano-electronics with unprecedented possibilities to control the gap by external stimuli. Strong quantum confinement results in extremely high exciton binding energies which forms an interesting platform for both fundamental studies and device applications. Breaking of spatial inversion symmetry in monolayers results in strong spin-valley coupling potentially leading to their use in valleytronics. Starting with the basic chemistry of transition metals, the reader is introduced to the rich field of transition metal dichalcogenides. After a chapter on three dimensional crystals and a description of top-down and bottom-up fabrication methods of few-layer and single layer structures, the fascinating world of two-dimensional TMDCs structures is presented with their unique atomic, electronic, and magnetic properties. The book covers in detail particular features associated with decreased dimensionality such as stability and phase-transitions in monolayers, the appearance of a direct gap, large binding energy of 2D excitons and trions and their dynamics, Raman scattering associated with decreased dimensionality, extraordinarily strong light-matter interaction, layer-dependent photoluminescence properties, new physics associated with the destruction of the spatial inversion symmetry of the bulk phase, spin-orbit and spin-valley couplings. The book concludes with chapters on engineered heterostructures and device applications such as a monolayer MoS2 transistor. Considering the explosive interest in physics and applications of two-dimensional materials, this book is a valuable source of information for material scientists and engineers working in the field as well as for the graduate students majoring in materials science.
Download or read book Semiconductor Photonics of Nanomaterials and Quantum Structures written by Arash Rahimi-Iman and published by Springer Nature. This book was released on 2021-04-23 with total page 288 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book introduces the wider field of functional nanomaterials sciences, with a strong emphasis on semiconductor photonics. Whether you are studying photonic quantum devices or just interested in semiconductor nanomaterials and their benefits for optoelectronic applications, this book offers you a pedagogical overview of the relevant subjects along with topical reviews. The book discusses different yet complementary studies in the context of ongoing international research efforts, delivering examples from both fundamental and applied research to a broad readership. In addition, a hand-full of useful optical techniques for the characterization of semiconductor quantum structures and materials are addressed. Moreover, nanostructuring methods for the production of low-dimensional systems, which exhibit advantageous properties predominantly due to quantum effects, are summarized. Science and engineering professionals in the interdisciplinary domains of nanotechnology, photonics, materials sciences, and quantum physics can familiarize themselves with selected highlights with eyes towards photonic applications in the fields of two-dimensional materials research, light–matter interactions, and quantum technologies.
Download or read book Two dimensional Coherent Spectroscopy of Monolayer Transition Metal Dichalcogenides written by Chandriker Kavir Dass and published by . This book was released on 2015 with total page 264 pages. Available in PDF, EPUB and Kindle. Book excerpt: Two-dimensional semiconductors have long been studied for their unique optical and electronic properties, but with the work of Novoselov and Geim on van der Waals materials, two-dimensional semiconductors have seen a surge of renewed interest. This dissertation focuses on monolayer transition metal dichalcogenides (TMDCs), a class of two-dimensional materials that can easily be fabricated by mechanical exfoliation, much like graphene. In their bulk form, these materials have indirect band gaps, but transition to direct gap semiconductors in the monolayer limit. The band-edge optical response of TMDCs, like WSe2 and MoS2, is dominated by exciton absorption occurring at the ±K-points of the Brillouin zone. Because of the unique electronic structure of these materials, these two points form distinct valleys in the band structure which can be exploited to produce valley polarization. Exciton quantum dynamics are characterized by two fundamental parameters, one of which is the dephasing rate, [gamma], which describes quantum dissipation arising from the interaction of the excitons with their environment (i.e. other excitons, impurities, etc...). This dissertation focuses on measuring the fundamental property of dephasing time (which is inversely proportional to the dephasing rate and homogeneous linewidth) in monolayer WSe2 through the use of two-dimensional coherent spectroscopy. Our measurements have revealed a homogeneous linewidth consistent with dephasing times in the sub-picosecond regime. We also characterize the role of exciton-exciton and exciton-phonon interactions, on the homogeneous linewidth, through excitation density and temperature dependent studies. These studies have revealed strong many-body effects and nonradiative population relaxation as the primary dephasing mechanisms. Microscopic calculations show that in perfect crystalline samples of monolayer TMDCs, the radiative lifetimes are also in the sub-picosecond regime due to the large oscillator strengths inherent in these materials. This result is consistent with the short dephasing times found experimentally.
Download or read book Quantum Theory of the Optical and Electronic Properties of Semiconductors written by Hartmut Haug and published by World Scientific. This book was released on 1994 with total page 496 pages. Available in PDF, EPUB and Kindle. Book excerpt: This textbook presents the basic elements needed to understand and engage in research in semiconductor physics. It deals with elementary excitations in bulk and low-dimensional semiconductors, including quantum wells, quantum wires and quantum dots. The basic principles underlying optical nonlinearities are developed, including excitonic and many-body plasma effects. The fundamentals of optical bistability, semiconductor lasers, femtosecond excitation, optical Stark effect, semiconductor photon echo, magneto-optic effects, as well as bulk and quantum-confined Franz-Keldysh effects are covered. The material is presented in sufficient detail for graduate students and researchers who have a general background in quantum mechanics.
Download or read book Excitonic Linewidth and Coherence Lifetime in Monolayer Transition Metal Dichalcogenides written by and published by . This book was released on 2016 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Atomically thin transition metal dichalcogenides are direct-gap semiconductors with strong light-matter and Coulomb interactions. The latter accounts for tightly bound excitons, which dominate their optical properties. Besides the optically accessible bright excitons, these systems exhibit a variety of dark excitonic states. They are not visible in the optical spectra, but can strongly influence the coherence lifetime and the linewidth of the emission from bright exciton states. We investigate the microscopic origin of the excitonic coherence lifetime in two representative materials (WS2 and MoSe2) through a study combining microscopic theory with spectroscopic measurements. We also show that the excitonic coherence lifetime is determined by phonon-induced intravalley scattering and intervalley scattering into dark excitonic states. Particularly, we identify exciton relaxation processes involving phonon emission into lower-lying dark states that are operative at all temperatures, in WS2.
Download or read book On Exciton Vibration and Exciton Photon Interactions in Organic Semiconductors written by Antonios M. Alvertis and published by Springer Nature. This book was released on 2021-10-25 with total page 213 pages. Available in PDF, EPUB and Kindle. Book excerpt: What are the physical mechanisms that underlie the efficient generation and transfer of energy at the nanoscale? Nature seems to know the answer to this question, having optimised the process of photosynthesis in plants over millions of years of evolution. It is conceivable that humans could mimic this process using synthetic materials, and organic semiconductors have attracted a lot of attention in this respect. Once an organic semiconductor absorbs light, bound pairs of electrons with positively charged holes, termed `excitons’, are formed. Excitons behave as fundamental energy carriers, hence understanding the physics behind their efficient generation and transfer is critical to realising the potential of organic semiconductors for light-harvesting and other applications, such as LEDs and transistors. However, this problem is extremely challenging since excitons can interact very strongly with photons. Moreover, simultaneously with the exciton motion, organic molecules can vibrate in hundreds of possible ways, having a very strong effect on energy transfer. The description of these complex phenomena is often beyond the reach of standard quantum mechanical methods which rely on the assumption of weak interactions between excitons, photons and vibrations. In this thesis, Antonios Alvertis addresses this problem through the development and application of a variety of different theoretical methods to the description of these strong interactions, providing pedagogical explanations of the underlying physics. A comprehensive introduction to organic semiconductors is followed by a review of the background theory that is employed to approach the relevant research questions, and the theoretical results are presented in close connection with experiment, yielding valuable insights for experimentalists and theoreticians alike.
Download or read book Two Dimensional Transition Metal Dichalcogenides written by Narayanasamy Sabari Arul and published by Springer. This book was released on 2019-07-30 with total page 355 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book presents advanced synthesis techniques adopted to fabricate two-dimensional (2D) transition metal dichalcogenides (TMDs) materials with its enhanced properties towards their utilization in various applications such as, energy storage devices, photovoltaics, electrocatalysis, electronic devices, photocatalysts, sensing and biomedical applications. It provides detailed coverage on everything from the synthesis and properties to the applications and future prospects of research in 2D TMD nanomaterials.
Download or read book Valleytronics In 2d Materials written by Kuan Eng Johnson Goh and published by World Scientific. This book was released on 2023-06-26 with total page 360 pages. Available in PDF, EPUB and Kindle. Book excerpt: Driven by the advent of two-dimensional materials, valleytronics is emerging as the next hot field of research in materials science. While the use of charge or spin degrees of freedom in electronic materials as information carriers is familiar and well-appreciated, employment of the valley degree of freedom as an information carrier has remained elusive for many decades. Shortly following the discovery of isolated graphene, 2D semiconductors such as transition metal dichalcogenides were also isolated and investigated. We now understand that these materials can have separately addressable valleys because each valley can be uniquely coupled to a spin state. This imparts the ability to address different valleys (like pseudospins) with electric field, magnetic field, or light, and there is now a real possibility to engineer practical devices based on using valley as the information carrier.Valleytronics in 2D Materials is the first book in the world on the topic of valleytronics. The reader is introduced to the concept via a brief history emphasizing the challenges that impeded its development for so long. We then dive into the valley physics of 2D semiconductors to explain the recent excitement in 2D valleytronics, the scientific investigations to confirm the addressable valleys, and the attempts to engineer valley devices for practical purposes. The text takes on a decidedly practical approach towards the subject, seeking to bring the reader quickly into the field by presenting the minimum theoretical basis for understanding the use of the valley degree of freedom in devices. A selection of key works establishing the scientific underpinnings of valley addressability and control are described to help the reader grasp the current stage of understanding, the technical foundations established, and the open questions. The renewal in valleytronics is yet unfinished, but with more than a decade of research and engineering efforts devoted in recent times, this book seeks to provide a timely reference for students, scientists and engineers to join this exciting journey and perhaps help to create the next disruption in information technology.
Download or read book Excitation Energy Transfer Processes in Condensed Matter written by Jai Singh and published by Springer Science & Business Media. This book was released on 2013-11-11 with total page 276 pages. Available in PDF, EPUB and Kindle. Book excerpt: Applying a unified quantum approach, contributors offer fresh insights into the theoretical developments in the excitation energy transfer processes in condensed matter. This comprehensive volume examines Frenkel and Wannier excitonic processes; rates of excitonic processes; theory of laser sputter and polymer ablation; and polarons, excitonic polarons and self-trapping.
Download or read book 2D Materials written by Phaedon Avouris and published by Cambridge University Press. This book was released on 2017-06-29 with total page 521 pages. Available in PDF, EPUB and Kindle. Book excerpt: Learn about the most recent advances in 2D materials with this comprehensive and accessible text. Providing all the necessary materials science and physics background, leading experts discuss the fundamental properties of a wide range of 2D materials, and their potential applications in electronic, optoelectronic and photonic devices. Several important classes of materials are covered, from more established ones such as graphene, hexagonal boron nitride, and transition metal dichalcogenides, to new and emerging materials such as black phosphorus, silicene, and germanene. Readers will gain an in-depth understanding of the electronic structure and optical, thermal, mechanical, vibrational, spin and plasmonic properties of each material, as well as the different techniques that can be used for their synthesis. Presenting a unified perspective on 2D materials, this is an excellent resource for graduate students, researchers and practitioners working in nanotechnology, nanoelectronics, nanophotonics, condensed matter physics, and chemistry.
Download or read book MoS2 written by Zhiming M. Wang and published by Springer Science & Business Media. This book was released on 2013-11-18 with total page 296 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book reviews the structure and electronic, magnetic, and other properties of various MoS2 (Molybdenum disulfide) nanostructures, with coverage of synthesis, Valley polarization, spin physics, and other topics. MoS2 is an important, graphene-like layered nano-material that substantially extends the range of possible nanostructures and devices for nanofabrication. These materials have been widely researched in recent years, and have become an attractive topic for applications such as catalytic materials and devices based on field-effect transistors (FETs) and semiconductors. Chapters from leading scientists worldwide create a bridge between MoS2 nanomaterials and fundamental physics in order to stimulate readers' interest in the potential of these novel materials for device applications. Since MoS2 nanostructures are expected to be increasingly important for future developments in energy and other electronic device applications, this book can be recommended for Physics and Materials Science and Engineering departments and as reference for researchers in the field.
Download or read book Coherent Light Matter Interactions in Monolayer Transition Metal Dichalcogenides written by Edbert Jarvis Sie and published by Springer. This book was released on 2017-11-11 with total page 142 pages. Available in PDF, EPUB and Kindle. Book excerpt: This thesis presents optical methods to split the energy levels of electronic valleys in transition-metal dichalcogenides (TMDs) by means of coherent light-matter interactions. The electronic valleys found in monolayer TMDs such as MoS2, WS2, and WSe2 are among the many novel properties exhibited by semiconductors when thinned down to a few atomic layers, and have have been proposed as a new way to carry information in next generation devices (so-called valleytronics). These valleys are, however, normally locked in the same energy level, which limits their potential use for applications. The author describes experiments performed with a pump-probe technique using transient absorption spectroscopy on MoS2 and WS2. It is demonstrated that hybridizing the electronic valleys with light allows one to optically tune their energy levels in a controllable valley-selective manner. In particular, by using off-resonance circularly polarized light at small detuning, one can tune the energy level of one valley through the optical Stark effect. Also presented within are observations, at larger detuning, of a separate contribution from the so-called Bloch--Siegert effect, a delicate phenomenon that has eluded direct observation in solids. The two effects obey opposite selection rules, enabling one to separate the two effects at two different valleys.
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 Introduction to Spectroscopic Ellipsometry of Thin Film Materials written by Andrew T. S. Wee and published by John Wiley & Sons. This book was released on 2022-03-08 with total page 213 pages. Available in PDF, EPUB and Kindle. Book excerpt: A one-of-a-kind text offering an introduction to the use of spectroscopic ellipsometry for novel material characterization In Introduction to Spectroscopic Ellipsometry of Thin Film Materials: Instrumentation, Data Analysis and Applications, a team of eminent researchers delivers an incisive exploration of how the traditional experimental technique of spectroscopic ellipsometry is used to characterize the intrinsic properties of novel materials. The book focuses on the scientifically and technologically important two-dimensional transition metal dichalcogenides (2D-TMDs), magnetic oxides like manganite materials, and unconventional superconductors, including copper oxide systems. The distinguished authors discuss the characterization of properties, like electronic structures, interfacial properties, and the consequent quasiparticle dynamics in novel quantum materials. Along with illustrative and specific case studies on how spectroscopic ellipsometry is used to study the optical and quasiparticle properties of novel systems, the book includes: Thorough introductions to the basic principles of spectroscopic ellipsometry and strongly correlated systems, including copper oxides and manganites Comprehensive explorations of two-dimensional transition metal dichalcogenides Practical discussions of single layer graphene systems and nickelate systems In-depth examinations of potential future developments and applications of spectroscopic ellipsometry Perfect for master’s- and PhD-level students in physics and chemistry, Introduction to Spectroscopic Ellipsometry of Thin Film Materials will also earn a place in the libraries of those studying materials science seeking a one-stop reference for the applications of spectroscopic ellipsometry to novel developed materials.
Download or read book 2D Excitonic Materials and Devices written by and published by Elsevier. This book was released on 2023-11-23 with total page 270 pages. Available in PDF, EPUB and Kindle. Book excerpt: Semiconductors and Semimetals series, highlights new advances in the field, with this new volume presenting interesting chapters. Each chapter is written by an international board of authors. - Provides the latest information on cancer research - Offers outstanding and original reviews on a range of cancer research topics - Serves as an indispensable reference for researchers and students alike
