Download or read book Quantum Criticality and Fermisurface Instabilities Investigation by Pressure and Quantum Oscillation Measurements on Ce and Ybbased Heavy Fermion Compounds written by Mounir Boukahil and published by . This book was released on 2014 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: The superconductivity had been thought to be incompatible with the magnetism, because the former originates from the weak attractive leading to the formation of Cooper pairs, whereas the latter is based on the strong Coulomb repulsive force, leading also to strong electronic correlations. Unconventional superconductors,which include heavy fermion systems, high-Tc cuprates, organic superconductors, and iron-pnictides, is a major topic of condensed matter physics. In all these systems, it has been understood that magnetism can even plays an important role for the pairing mechanism, so that both phenomena can coexist and even favour each other.Our target is on heavy fermion systems, namely uranium and rare earth compounds, where the 5f or 4f electrons which have a dual nature (itinerant/localized), play an important role. More precisely, we will focus on the ferromagnetic superconductors and their quantum criticality. In this field, new materials open new frontiers of research. The student will participate in this stream. He will learn and develop the fundamental crystal growth techniques, such as Czochralski, flux, and Bridgeman method. Since high quality single crystals are essential to elucidate the superconducting properties, a lot of efforts will be devoted to improve the quality of the samples. The next target is the quantum oscillation measurements, which allow a detailed microscopic observation of the heavy electronic state and of the topology of the Fermi surface. They require both very low temperature and high fields, like the study of the field induced superconducting phases in these compounds (like URhGe or UCoGe). The student will perform the measurements under extreme conditions, namely high fields up to 15T in SPSMS, or up to 30T in LNCMI, at low temperatures down to 30 mK, and high pressure up to 3 GPa.From the educational point of view, it is ideal that the student starts to synthesize a material, characterizes it, performs the low temperature measurements by him/herself throughout the PhD period, and get used to the exciting measurements under extreme conditions in a large scale facility like the LNCMI. Such a wide spectrum is rather rare in Europe, but our group ("SPSMS/LNCMI) can provide such a unique opportunity, helping the student to become an independent researcher. It should be noted that the experiments in SPSMS and LNCMI are quite complementary each other. For quantum oscillation study, high fields, low temperatures and high quality singles are inevitably important. In general, the precise measurements at high fields up to 15T would be enough in order to determine the Fermi surface topology and the effective mass, which canbe done in SPSMS. However, the specific case, such as Lifshitz transition, field induced quantum critical phenomena, requires higher fields than 15T, which can be achieved by the resistive magnet in LNCMI.This project is supported by the ANR (CORMAT, SINUS) and the ERC starting grant “NewHeavyFermion”.Recently in SPSMS we purchased a top-loading dilution refrigerator for the quantum oscillation measurements, and started the installation. By the end of this summer, hopefully we detect the first de Haas-van Alphen signal at high fields up to 15T and at temperatures down to 30mK. Furthermore, we started to install the flux crystal growth equipment this month, involving the reconstruction of the room for the safe treatment of uranium compounds.
Download or read book Yb based Heavy Fermion Compounds and Field Tuned Quantum Criticality written by Eundeok Mun and published by . This book was released on 2010 with total page 200 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Quantum Critical Phenomena of Valence Transition written by Shinji Watanabe and published by Springer Nature. This book was released on 2024-01-27 with total page 220 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book comprehensively presents an unconventional quantum criticality caused by valence fluctuations, which offers theoretical understanding of unconventional Fermi-liquid properties in cerium- and ytterbium-based heavy fermion metals including CeCu2(Si,Ge)2 and CeRhIn5 under pressure, and quasicrystal β-YbAlB4 and Yb15Al34Au51. The book begins with an introduction to fundamental concepts for heavy fermion systems, valence fluctuation, and quantum phase transition, including self-consistent renormalization group theory. A subsequent chapter is devoted to a comprehensive description of the theory of the unconventional quantum criticality based on a valence transition, featuring explicit temperature dependence of various physical quantities, which allows for comparisons to relevant experiments. Lastly, it discusses how ubiquitous the valence fluctuation is, presenting candidate materials not only in heavy fermions, but also in strongly correlated electrons represented by high-Tc superconductor cuprates. Introductory chapters provide useful materials for learning fundamentals of heavy fermion systems and their theory. Further, experimental topics relevant to valence fluctuations are valuable resources for those who are new to the field to easily catch up with experimental background and facts.
Download or read book Quantum Oscillations in the Heavy fermion Compound YbPtBi written by and published by . This book was released on 2015 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: We present quantum oscillations observed in the heavy-fermion compound YbPtBi in magnetic fields far beyond its field-tuned, quantum critical point. Quantum oscillations are observed in magnetic fields as low as 60 kOe at 60 mK and up to temperatures as high as 3 K, which confirms the very high quality of the samples as well as the small effective mass of the conduction carriers far from the quantum critical point. Although the electronic specific heat coefficient of YbPtBi reaches ~7.4 J/molK2 in zero field, which is one of the highest effective mass values among heavy-fermion systems, we suppress it quickly by an applied magnetic field. The quantum oscillations were used to extract the quasiparticle effective masses of the order of the bare electron mass, which is consistent with the behavior observed in specific heat measurements. Furthermore, such small effective masses at high fields can be understood by considering the suppression of Kondo screening.
Download or read book Heavy Fermions Quantum Criticality and Unconventional Superconductivity in Filled Skutterudites and Related Materials written by and published by . This book was released on 2015 with total page 6 pages. Available in PDF, EPUB and Kindle. Book excerpt: The main goal of this program was to explore the possibility of novel states and behaviors in Pr-based system exhibiting quantum critical behavior, PrOs4Sb12. Upon small changes of external parameter, such as magnetic field, physical properties of PrOs4Sb12 are drastically altered from those corresponding to a superconductor, to heavy fermion, to field-induced ordered phase with primary quadrupolar order parameter. All these states are highly unconventional and not understood in terms of current theories thus offer an opportunity to expand our knowledge and understanding of condensed matter. At the same time, these novel states and behaviors are subjects to intense international controversies. In particular, two superconducting phases with different transition temperatures were observed in some samples and not observed in others leading to speculations that sample defects might be partially responsible for these exotic behaviors. This work clearly established that crystal disorder is important consideration, but contrary to current consensus this disorder suppresses exotic behavior. Superconducting properties imply unconventional inhomogeneous state that emerges from unconventional homogeneous normal state. Comprehensive structural investigations demonstrated that upper superconducting transition is intrinsic, bulk, and unconventional. The high quality of in-house synthesized single crystals was indirectly confirmed by de Haas-van Alphen quantum oscillation measurements. These measurements, for the first time ever reported, spanned several different phases, offering unprecedented possibility of studying quantum oscillations across phase boundaries.
Download or read book Heavy Fermion Superconductivity and Quantum Criticality in Ce and Pu Based 115 Materials written by 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 Quantum Critical Fluctuations in the Heavy Fermion Compound Ce Ni 0 935 Pd 0 065 2 Ge 2 written by and published by . This book was released on 2014 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: In electric resistivity, specific heat, magnetic susceptibility, and inelastic neutron scattering experiments were performed on a single crystal of the heavy fermion compound Ce(Ni0.935Pd0.065)2Ge2 in order to study the spin fluctuations near an antiferromagnetic (AF) quantum critical point (QCP). The resistivity and the specific heat coefficient for T ≤ 1 K exhibit the power law behavior expected for a 3D itinerant AF QCP ([rho](T) ~ T3/2 and [gamma](T) ~ [gamma]0 - bT1/2). However, for 2 ≤ T ≤ 10 K, the susceptibility and specific heat vary as log T and the resistivity varies linearly with temperature. In spite of the fact that the resistivity and specific heat exhibit the non-Fermi liquid behavior expected at a QCP, the correlation length, correlation time, and staggered susceptibility of the spin fluctuations remain finite at low temperature. Here, we suggest that these deviations from the divergent behavior expected for a QCP may result from alloy disorder.
Download or read book Quantum Critical Fluctuations in the Heavy Fermion Compound Ce Ni0 935Pd0 065 2Ge2 written by and published by . This book was released on 2014 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Electric resistivity, specific heat, magnetic susceptibility, and inelastic neutron scattering experiments were performed on a single crystal of the heavy fermion compound Ce(Ni0.935Pd0.065)2Ge2 in order to research the spin fluctuations near an antiferromagnetic (AF) quantum critical point (QCP). The resistivity and the specific heat coefficient for T ≤ 1 K exhibit the power law behavior expected for a 3D itinerant AF QCP ([rho](T) ~ T3/2 and [gamma](T) ~ [gamma]0 - bT1/2). However, for 2 ≤ T ≤ 10 K, the susceptibility and specific heat vary as log T and the resistivity varies linearly with temperature. In addition, despite the fact that the resistivity and specific heat exhibit the non-Fermi liquid behavior expected at a QCP, the correlation length, correlation time, and staggered susceptibility of the spin fluctuations remain finite at low temperature. In conclusion, we suggest that these deviations from the divergent behavior expected for a QCP may result from alloy disorder.
Download or read book Quantum Critical Behavior in the Heavy Fermion Compounds YbRh 2 Si 2 and CeIn 3 x Sn X written by Jeroen Custers and published by . This book was released on 2004 with total page 154 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Measurements of Landau Quantum Oscillations in Heavy Fermion Systems written by Robert W. Hill and published by . This book was released on 1996 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Quantum Criticality in the Heavy Fermion Superconductor Cerium cobalt indium microform written by Johnpierre Paglione and published by Library and Archives Canada = Bibliothèque et Archives Canada. This book was released on 2005 with total page 168 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Novel Superconductivity written by Stuart A. Wolf and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 1086 pages. Available in PDF, EPUB and Kindle. Book excerpt: The Novel Mechanisms of Superconductivity Conference was initially conceived in the early part of 1986 as a small, 2-1/2 day workshop of 40-70 scientists, both theorists and experimentalists interested in exploring the possible evidence for exotic, non phononic superconductivity. Of course, the historic discoveries of high temperature oxide superconductors by Bednorz and Mftller and the subsequent enhancements by the Houston/Alabama groups made such a small conference impractical. The conference necessarily had to expand, 2-1/2 days became 4-1/2 days and superconductivity in the high Tc oxides became the largest single topic in the workshop. In fact, this conference became the first major conference on this topic and thus, these proceedings are also the first maj or publication. However, heavy fermion, organic and low carrier concentration superconductors remained a very important part of this workshop and articles by the leaders in these fields are included in these proceedings. Ultimately the workshop hosted rearly 400 scientists, students and media including representatives from the maj or research groups in the U.S., Europe, Japan and the Soviet Union.
Download or read book Quantum Magnetism written by Ulrich Schollwöck and published by Springer. This book was released on 2008-05-14 with total page 488 pages. Available in PDF, EPUB and Kindle. Book excerpt: Closing a gap in the literature, this volume is intended both as an introductory text at postgraduate level and as a modern, comprehensive reference for researchers in the field. Provides a full working description of the main fundamental tools in the theorists toolbox which have proven themselves on the field of quantum magnetism in recent years. Concludes by focusing on the most important cuurent materials form an experimental viewpoint, thus linking back to the initial theoretical concepts.
Download or read book The Kondo Problem to Heavy Fermions written by Alexander Cyril Hewson and published by Cambridge University Press. This book was released on 1997-04-28 with total page 476 pages. Available in PDF, EPUB and Kindle. Book excerpt: The behaviour of magnetic impurities in metals has posed problems to challenge the condensed matter theorist over the past 30 years. This book deals with the concepts and techniques which have been developed to meet this challenge, and with their application to the interpretation of experiments. This book will be of interest to condensed matter physicists, particularly those interested in strong correlation problems. The detailed discussions of advanced many-body techniques should make it of interest to theoretical physicists in general.
Download or read book Integrated Design and Simulation of Chemical Processes written by Alexandre C. Dimian and published by Elsevier. This book was released on 2014-09-18 with total page 887 pages. Available in PDF, EPUB and Kindle. Book excerpt: This comprehensive work shows how to design and develop innovative, optimal and sustainable chemical processes by applying the principles of process systems engineering, leading to integrated sustainable processes with 'green' attributes. Generic systematic methods are employed, supported by intensive use of computer simulation as a powerful tool for mastering the complexity of physical models. New to the second edition are chapters on product design and batch processes with applications in specialty chemicals, process intensification methods for designing compact equipment with high energetic efficiency, plantwide control for managing the key factors affecting the plant dynamics and operation, health, safety and environment issues, as well as sustainability analysis for achieving high environmental performance. All chapters are completely rewritten or have been revised. This new edition is suitable as teaching material for Chemical Process and Product Design courses for graduate MSc students, being compatible with academic requirements world-wide. The inclusion of the newest design methods will be of great value to professional chemical engineers. Systematic approach to developing innovative and sustainable chemical processes Presents generic principles of process simulation for analysis, creation and assessment Emphasis on sustainable development for the future of process industries
Download or read book Stochastic Transport in Complex Systems written by Andreas Schadschneider and published by Elsevier. This book was released on 2010-10-01 with total page 585 pages. Available in PDF, EPUB and Kindle. Book excerpt: The first part of the book provides a pedagogical introduction to the physics of complex systems driven far from equilibrium. In this part we discuss the basic concepts and theoretical techniques which are commonly used to study classical stochastic transport in systems of interacting driven particles. The analytical techniques include mean-field theories, matrix product ansatz, renormalization group, etc. and the numerical methods are mostly based on computer simulations. In the second part of the book these concepts and techniques are applied not only to vehicular traffic but also to transport and traffic-like phenomena in living systems ranging from collective movements of social insects (for example, ants) on trails to intracellular molecular motor transport. These demonstrate the conceptual unity of the fundamental principles underlying the apparent diversity of the systems and the utility of the theoretical toolbox of non-equilibrium statistical mechanics in interdisciplinary research far beyond the traditional disciplinary boundaries of physics. Leading industry experts provide a broad overview of the interdisciplinary nature of physics Presents unified descriptions of intracellular, ant, and vehicular traffic from a physics point of view Applies theoretical methods in practical everyday situations Reference and guide for physicists, engineers and graduate students
Download or read book Computer Aided Property Estimation for Process and Product Design written by Georgios M. Kontogeorgis and published by Elsevier. This book was released on 2004-06-30 with total page 437 pages. Available in PDF, EPUB and Kindle. Book excerpt: Properties of chemical compounds and their mixtures are needed in almost every aspect of process and product design. When the use of experimental data is not possible, one of the most widely used options in the use of property estimation models. Computer Aided Property Estimation for Process and Product Design provides a presentation of the most suitable property estimation models available today as well as guidelines on how to select an appropriate model. Problems that users are faced with, such as: which models to use and what their accuracy is, are addressed using a systematical approach to property estimation. The volume includes contributions from leading experts from academia and industry. A wide spectrum of properties and phase equilibria types is covered, making it indispensable for research, development and educational purposes. * This book presents the latest developments in computational modelling for thermodynamic property estimation.* It combines theory with practice and includes illustrative examples of software applications. * The questions users of property models are faced with are addressed comprehensively.
