Download or read book On the Nature of Charge Density Waves Superconductivity and Their Interplay in 1T TiSe2 written by Chuan Chen and published by Springer Nature. This book was released on 2019-09-27 with total page 105 pages. Available in PDF, EPUB and Kindle. Book excerpt: This thesis presents analytical theoretical studies on the interplay between charge density waves (CDW) and superconductivity (SC) in the actively studied transition-metal dichalcogenide 1T-TiSe2. It begins by reapproaching a years-long debate over the nature of the phase transition to the commensurate CDW (CCDW) state and the role played by the intrinsic tendency towards excitonic condensation in this system. A Ginzburg-Landau phenomenological theory was subsequently developed to understand the experimentally observed transition from commensurate to incommensurate CDW (ICDW) order with doping or pressure, and the emergence of a superconducting dome that coexists with ICDW. Finally, to characterize microscopically the effects of the interplay between CDW and SC, the spectrum of CDW fluctuations beyond mean-field was studied in detail. In the aggregate, the work reported here provides an encompassing understanding of what are possibly key microscopic underpinnings of the CDW and SC physics in TiSe2.
Download or read book On the Nature of Charge Density Waves Superconductivity and Their Interplay in 1T TiSe2 written by Chuan Chen and published by . This book was released on 2019 with total page 105 pages. Available in PDF, EPUB and Kindle. Book excerpt: This thesis presents analytical theoretical studies on the interplay between charge density waves (CDW) and superconductivity (SC) in the actively studied transition-metal dichalcogenide 1T-TiSe2. It begins by reapproaching a years-long debate over the nature of the phase transition to the commensurate CDW (CCDW) state and the role played by the intrinsic tendency towards excitonic condensation in this system. A Ginzburg-Landau phenomenological theory was subsequently developed to understand the experimentally observed transition from commensurate to incommensurate CDW (ICDW) order with doping or pressure, and the emergence of a superconducting dome that coexists with ICDW. Finally, to characterize microscopically the effects of the interplay between CDW and SC, the spectrum of CDW fluctuations beyond mean-field was studied in detail. In the aggregate, the work reported here provides an encompassing understanding of what are possibly key microscopic underpinnings of the CDW and SC physics in TiSe2.
Download or read book Interplay of Superconductivity Magnetism and Density Waves in Rare earth Tritellurides and Iron based Superconducting Materials written by Diego Andrés Zocco and published by . This book was released on 2011 with total page 154 pages. Available in PDF, EPUB and Kindle. Book excerpt: Superconductivity, charge- and spin-density waves are collective electronic phenomena that originate from electron-electron and electron-phonon interactions, and the concept of Fermi surface competition between these collective states is one of the most fundamental problems of condensed matter physics. High pressures provide a clean method to tune the electronic properties that determine the superconducting, magnetic or charge-ordered ground states of complex materials. The charge-density wave, magnetic and superconducting ordered states of the rare-earth tritellurides system, and the interplay between the spin-density wave, localized magnetism and superconductivity in the recently discovered Fe-based high-temperature superconductors, have been investigated under extreme conditions of pressure, magnetic field and low temperatures.
Download or read book Density Waves In Solids written by George Gruner and published by CRC Press. This book was released on 2018-03-08 with total page 288 pages. Available in PDF, EPUB and Kindle. Book excerpt: ?Density Waves in Solids is written for graduate students and scientists interested in solid-state sciences. It discusses the theoretical and experimental state of affairs of two novel types of broken symmetry ground states of metals, charge, and spin density waves. These states arise as the consequence of electron-phonon and electron-electron interactions in low-dimensional metals.Some fundamental aspects of the one-dimensional electron gas, and of the materials with anisotropic properties, are discussed first. This is followed by the mean field theory of the phases transitions?discussed using second quantized formalism?together with the various experimental observations on the transition and on the ground states. Fluctuation effects and the collective excitations are reviewed next, using the Ginzburg-Landau formalism, followed by the review of the interaction of these states with the underlying lattice and with impurities. The final chapters are devoted to the response of the ground states to external perturbations.
Download or read book Emergent States in Photoinduced Charge Density Wave Transitions written by Alfred Zong and published by Springer Nature. This book was released on 2021-09-17 with total page 234 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book advances understanding of light-induced phase transitions and nonequilibrium orders that occur in a broken-symmetry system. Upon excitation with an intense laser pulse, materials can undergo a nonthermal transition through pathways different from those in equilibrium. The mechanism underlying these photoinduced phase transitions has long been researched, but many details in this ultrafast, non-adiabatic regime still remain to be clarified. The work in this book reveals new insights into this phenomena via investigation of photoinduced melting and recovery of charge density waves (CDWs). Using several time-resolved diffraction and spectroscopic techniques, the author shows that the light-induced melting of a CDW is characterized by dynamical slowing-down, while the restoration of the symmetry-breaking order features two distinct timescales: A fast recovery of the CDW amplitude is followed by a slower re-establishment of phase coherence, the latter of which is dictated by the presence of topological defects in the CDW. Furthermore, after the suppression of the original CDW by photoexcitation, a different, competing CDW transiently emerges, illustrating how a hidden order in equilibrium can be unleashed by a laser pulse. These insights into CDW systems may be carried over to other broken-symmetry states, such as superconductivity and magnetic ordering, bringing us one step closer towards manipulating phases of matter using a laser pulse.
Download or read book Charge Density Waves in 2D Transition Metal Dichalcogenides written by Anton A. Anikin and published by . This book was released on 2021 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: At low temperatures, the electronic structure of metals becomes unstable, and instabilities often develop correlated electronic states, decreasing the number of free carriers. One of these correlated states is a charge density wave state. It usually arises under the interaction of free carriers with phonons, and it is manifested as a superstructure over the original crystal lattice. The charge density wave state presents distinguishable experimental fingerprints in many physical properties of the crystal, spontaneously breaking its translational symmetry. The physics of the charge density wave is well established in the case of a one-dimensional metal; however, there are lot of open issues, when describing the systems of higher dimensions. The charge density wave state could potentially be utilized in low-energy electronic devices. Transition metal dichalcogenides are quasi two-dimensional materials, that exhibit a correlated electronic behavior, such as the superconductivity and the charge density wave. Due to their simple crystalline structures, nearly perfect crystals can be grown, and the electronic correlations can be studied in the absence of any disorder. An example of this class of materials is 2H-NbSe2, that undergoes both the charge density wave (T_CDW=33.5 K) and superconducting (T_SC=7.2 K) transitions. The first part of this work is focused on the single crystal growth, electronic transport characterization, and results of ultrafast transient reflectivity measurements of 2H-NbSe2 single crystals. Coherent lattice dynamics and characteristic relaxation times of photoexcited charge carriers have been extracted from the broadband transient optical spectroscopy. A wide temporal profile gives opportunity to track multiple ultrafast phenomena within the same experiment from 50 fs to few nanoseconds. The physical mechanisms leading to the charge density wave condensation are being discussed here. The second part of this work is focused on a studying of the temperature hysteresis in electrical transport properties in freshly grown undoped and doped 1T-TiSe2 single crystals. This transition metal dichalcogenide undergoes a chiral charge density wave at low temperatures (T_CDW=202 K). An irreversible behavior of electrical properties upon the thermocycling indicates an existence of metastable states in the charge density wave phase, and it is commonly attributed to additional phase transitions. The absence of strong experimental evidence of these transitions is collaborated with an opened dispute on the nature of charge density wave state in this material. Physical origins of this phenomenon, including a complex charge density wave domain structure of 1T-TiSe2, are being discussed in the second part of the work.
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 Interplay of Charge Density Modulations and Superconductivity written by Jason Wayne Sadowski and published by . This book was released on 2011 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
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 Non Centrosymmetric Superconductors written by Ernst Bauer and published by Springer Science & Business Media. This book was released on 2012-01-10 with total page 360 pages. Available in PDF, EPUB and Kindle. Book excerpt: Superconductivity in materials without inversion symmetry in the respective crystal structures occurs in the presence of antisymmetric spin-orbit coupling as a consequence of an emerging electric field gradient. The superconducting condensate is then a superposition of spin-singlet and spin-triplet Cooper pairs. This scenario accounts for various experimental findings such as nodes in the superconducting gap or extremely large upper critical magnetic fields. Spin-triplet pairing can occur in non-centrosymmetric superconductors in spite of Anderson’s theorem that spin-triplet pairing requires a crystal structure that exhibits inversion symmetry. This book, authored and edited by leading researchers in the field, is both an introduction to and overview on this exciting branch of novel superconductors. Its self-contained and tutorial style makes it particularly suitable for self-study and as source of teaching material for special seminars and courses. At the same time it constitutes an up-to-date and authoritative reference for anyone working in this exciting field.
Download or read book Charge density waves and Superconductivity in Anisotropic Conductors written by John David Kulick and published by . This book was released on 1981 with total page 342 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Physics Briefs written by and published by . This book was released on 1989 with total page 1542 pages. Available in PDF, EPUB and Kindle. Book excerpt:
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 Quantum Theory of Solids written by R. E. Peierls and published by Clarendon Press. This book was released on 1996-08-15 with total page 238 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book develops the subject from the basic principles of quantum mechanics. The emphasis is on a single statement of the ideas underlying the various approximations that have to be used and care is taken to separate sound arguments from conjecture. This book is written for the student of theoretical physics who wants to work in the field of solids and for the experimenter with a knowledge of quantum theory who is not content to take other people's arguments for granted. The treatment covers the electron theory of metals as well as the dynamics of crystals, including the author's work on the thermal conductivity of crystals which has been previously published in English.
Download or read book Quantum Confined Excitons in 2 Dimensional Materials written by Carmen Palacios-Berraquero and published by Springer. This book was released on 2018-11-02 with total page 125 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book presents the first established experimental results of an emergent field: 2-dimensional materials as platforms for quantum technologies, specifically through the optics of quantum-confined excitons. It also provides an extensive review of the literature from a number of disciplines that informed the research, and introduces the materials of focus – 2d Transition Metal Dichalcogenides (2d-TMDs) – in detail, discussing electronic and chemical structure, excitonic behaviour and response to strain. This is followed by a brief overview of quantum information technologies, including concepts such as single-photon sources and quantum networks. The methods chapter addresses quantum optics techniques and 2d-material processing, while the results section shows the development of a method to deterministically create quantum dots (QDs) in the 2d-TMDs, which can trap single-excitons; the fabrication of atomically thin quantum light-emitting diodes to induce all-electrical single-photon emission from the QDs, and lastly, the use of devices to controllably trap single-spins in the QDs –the first step towards their use as optically-addressable matter qubits.
Download or read book Theory of Quantum Liquids written by Philippe Nozieres and published by Westview Press. This book was released on 1994-06-21 with total page 210 pages. Available in PDF, EPUB and Kindle. Book excerpt: Originally published as two separate volumes, The Theory of Quantum Liquids is a classic text that attempts to describe the qualitative and unifying aspects of an extremely broad and diversified field. Volume I deals with ‘normal’ Fremi liquids, such as 3He and electrons in metals. Volume II consists of a detailed treatment of Bose condensation and liquid 4He, including the development of a Bose liquid theory and a microscopic basis for the two-fluid model, and the description of the elementary excitations of liquid HeII.
Download or read book True Genius written by Vicki Daitch and published by Joseph Henry Press. This book was released on 2002-10-28 with total page 489 pages. Available in PDF, EPUB and Kindle. Book excerpt: What is genius? Define it. Now think of scientists who embody the concept of genius. Does the name John Bardeen spring to mind? Indeed, have you ever heard of him? Like so much in modern life, immediate name recognition often rests on a cult of personality. We know Einstein, for example, not just for his tremendous contributions to science, but also because he was a character, who loved to mug for the camera. And our continuing fascination with Richard Feynman is not exclusively based on his body of work; it is in large measure tied to his flamboyant nature and offbeat sense of humor. These men, and their outsize personalities, have come to erroneously symbolize the true nature of genius and creativity. We picture them born brilliant, instantly larger than life. But is that an accurate picture of genius? What of others who are equal in stature to these icons of science, but whom history has awarded only a nod because they did not readily engage the public? Could a person qualify as a bona fide genius if he was a regular Joe? The answer may rest in the story of John Bardeen. John Bardeen was the first person to have been awarded two Nobel Prizes in the same field. He shared one with William Shockley and Walter Brattain for the invention of the transistor. But it was the charismatic Shockley who garnered all the attention, primarily for his Hollywood ways and notorious views on race and intelligence. Bardeen's second Nobel Prize was awarded for the development of a theory of superconductivity, a feat that had eluded the best efforts of leading theorists-including Albert Einstein, Neils Bohr, Werner Heisenberg, and Richard Feynman. Arguably, Bardeen's work changed the world in more ways than that of any other scientific genius of his time. Yet while every school child knows of Einstein, few people have heard of John Bardeen. Why is this the case? Perhaps because Bardeen differs radically from the popular stereotype of genius. He was a modest, mumbling Midwesterner, an ordinary person who worked hard and had a knack for physics and mathematics. He liked to picnic with his family, collaborate quietly with colleagues, or play a round of golf. None of that was newsworthy, so the media, and consequently the public, ignored him. John Bardeen simply fits a new profile of genius. Through an exploration of his science as well as his life, a fresh and thoroughly engaging portrait of genius and the nature of creativity emerges. This perspective will have readers looking anew at what it truly means to be a genius.
