Quantum Phase Transitions in the Presence of Disorder and Dissipation PDF Download
Are you looking for read ebook online? Search for your book and save it on your Kindle device, PC, phones or tablets. Download Quantum Phase Transitions in the Presence of Disorder and Dissipation PDF full book. Access full book title Quantum Phase Transitions in the Presence of Disorder and Dissipation by Chetan Vyankatesh Kotabage. Download full books in PDF and EPUB format.
Author: Chetan Vyankatesh Kotabage Publisher: ISBN: Category : Phase transformations (Statistical physics) Languages : en Pages : 196
Book Description
"A quantum phase transition is a phase transition at absolute zero occurring under variations in an external non-thermal parameter such as magnetic field or pressure. Quantum phase transitions are one among the important topics currently investigated in condensed matter physics. They are observed in various systems, e.g., in the ferromagnetic-paramagnetic phase transition in LiHoF4 or in the superconductor-metal phase transition in nanowires. A particular class of quantum phase transitions, which is phase transitions in the presence of disorder and dissipation, is investigated here. An example of this class is the ferromagnetic-paramagnetic phase transition in Ni[subscript 1-x]V[subscript x] or CePd[subscript 1-x'Rh[subscript x] caused by variations in chemical composition. In these system [sic], disorder is due to random positions of doping element and the dynamics of order-parameter fluctuations is dissipative due to conduction electrons. These quantum phase transitions are explained using the following approach: The Landau_Ginzberg_Wilson functional, which is derived from a microscopic Hamiltonian, is treated by the strong-disorder renormalization group method. For ohmic damping, phase transitions are strongly influenced by disorder and the critical point is an infinite-randomness fixed point, which is in the universality class same as that of the random transverse-field Ising model. The scaling form of observable quantities is activated type rather than conventional power-law type. For superohmic damping, the strong-disorder renormalization group method yields one of the recursion relationships different from ohmic damping. This difference indicates a more conventional transition for superohmic damping"--Abstract, leaf iii.
Author: Chetan Vyankatesh Kotabage Publisher: ISBN: Category : Phase transformations (Statistical physics) Languages : en Pages : 196
Book Description
"A quantum phase transition is a phase transition at absolute zero occurring under variations in an external non-thermal parameter such as magnetic field or pressure. Quantum phase transitions are one among the important topics currently investigated in condensed matter physics. They are observed in various systems, e.g., in the ferromagnetic-paramagnetic phase transition in LiHoF4 or in the superconductor-metal phase transition in nanowires. A particular class of quantum phase transitions, which is phase transitions in the presence of disorder and dissipation, is investigated here. An example of this class is the ferromagnetic-paramagnetic phase transition in Ni[subscript 1-x]V[subscript x] or CePd[subscript 1-x'Rh[subscript x] caused by variations in chemical composition. In these system [sic], disorder is due to random positions of doping element and the dynamics of order-parameter fluctuations is dissipative due to conduction electrons. These quantum phase transitions are explained using the following approach: The Landau_Ginzberg_Wilson functional, which is derived from a microscopic Hamiltonian, is treated by the strong-disorder renormalization group method. For ohmic damping, phase transitions are strongly influenced by disorder and the critical point is an infinite-randomness fixed point, which is in the universality class same as that of the random transverse-field Ising model. The scaling form of observable quantities is activated type rather than conventional power-law type. For superohmic damping, the strong-disorder renormalization group method yields one of the recursion relationships different from ohmic damping. This difference indicates a more conventional transition for superohmic damping"--Abstract, leaf iii.
Author: Fawaz Y. Hrahsheh Publisher: ISBN: Category : Ferromagnetism Languages : en Pages : 146
Book Description
"Disorder can have a wide variety of consequences for the physics of phase transitions. Some transitions remain unchanged in the presence of disorder while others are completely destroyed. In this thesis we study the effects of disorder on several classical and quantum phase transitions in condensed matter systems. After a brief introduction, we study the ferromagnetic phase transition in a randomly layered Heisenberg magnet using large-scale Monte-Carlo simulations. Our results provide numerical evidence for the exotic infinite-randomness scenario. We study classical and quantum smeared phase transitions in substitutional alloys A[subscript 1-x]B[subscript x]. Our results show that the disorder completely destroys the phase transition with a pronounced tail of the ordered phase developing for all compositions x
Author: Subir Sachdev Publisher: Cambridge University Press ISBN: 113950021X Category : Science Languages : en Pages : 521
Book Description
Describing the physical properties of quantum materials near critical points with long-range many-body quantum entanglement, this book introduces readers to the basic theory of quantum phases, their phase transitions and their observable properties. This second edition begins with a new section suitable for an introductory course on quantum phase transitions, assuming no prior knowledge of quantum field theory. It also contains several new chapters to cover important recent advances, such as the Fermi gas near unitarity, Dirac fermions, Fermi liquids and their phase transitions, quantum magnetism, and solvable models obtained from string theory. After introducing the basic theory, it moves on to a detailed description of the canonical quantum-critical phase diagram at non-zero temperatures. Finally, a variety of more complex models are explored. This book is ideal for graduate students and researchers in condensed matter physics and particle and string theory.
Author: Lincoln Carr Publisher: CRC Press ISBN: 1439802610 Category : Science Languages : en Pages : 756
Book Description
Quantum phase transitions (QPTs) offer wonderful examples of the radical macroscopic effects inherent in quantum physics: phase changes between different forms of matter driven by quantum rather than thermal fluctuations, typically at very low temperatures. QPTs provide new insight into outstanding problems such as high-temperature superconductivit
Author: Yurij Holovatch Publisher: World Scientific ISBN: 9789812565440 Category : Science Languages : en Pages : 312
Book Description
This book is the second volume of review papers on advanced problems of phase transitions and critical phenomena, following the success of the first volume in 2004. Broadly, the volume aims to demonstrate that the phase transition theory, which experienced its ''golden age'' during the 70s and 80s, is far from over and there is still a good deal of work to be done, both at the fundamental level and in respect of applications.The topics presented in this volume include: critical behavior as explained by the non-perturbative renormalization group, critical dynamics, a spacetime approach to phase transitions, self-organized criticality, and exactly solvable models of phase transitions in strongly correlated systems. As the first volume, this book is based on the review lectures that were given in Lviv (Ukraine) at the OC Ising lecturesOCO OCo a traditional annual workshop on phase transitions and critical phenomena which brings together scientists working in the field with university students and those who are interested in the subject."
Author: Manal M. Al-Ali Publisher: ISBN: Category : Nonequilibrium statistical mechanics Languages : en Pages : 119
Book Description
"This thesis investigates the influence of random disorder and dissipation on zero-temperature quantum phase transitions. Both phenomena can fundamentally change the character of the phases of a quantum many-particle system and of the transitions between them. If dissipation and disorder occur simultaneously in a system undergoing a quantum phase transition, particularly strong effects can be expected. In the first paper reproduced in this thesis, we study a single quantum rotor coupled to a sub-Ohmic dissipative bath. We find that this system undergoes a quantum phase transition from a delocalized phase to a localized phase as the dissipation strength is increased. We determine the exact critical behavior of this transition; it agrees with that of the corresponding long-range interacting classical model. Therefore, the quantum-to-classical mapping is valid for the sub-Ohmic rotor model. In the second paper, we investigate the influence of sub-Ohmic dissipation on randomly diluted quantum Ising and rotor models. We find that the zero-temperature quantum phase transition across the lattice percolation threshold separates an unusual super-paramagnetic cluster phase from an inhomogeneous ferromagnetic phase. We determine the low-temperature thermodynamic behavior in both phases, and we relate our results to the smeared transition scenario for disordered quantum phase transitions. In the last paper, the influence of Ohmic dissipation on the random transverse-field Ising chain is studied by means of large-scale Monte-Carlo simulations. Our simulations show that Ohmic dissipation destroys the infinite-randomness quantum critical point of the dissipationless system. Instead, the quantum phase transition between the paramagnetic and ferromagnetic phases is smeared, as predicted by a recent strong-disorder renormalization group approach"--Abstract, page iv.
Author: David Nozadze Publisher: ISBN: Category : Ferromagnetism Languages : en Pages : 152
Book Description
"We study the effects of quenched weak disorder on quantum phase transitions in disordered magnets. The presence of disorder in the system can lead to a variety of exotic phenomena, e.g., the smearing of transitions or quantum Griffiths singularities. Phase transitions are smeared if individual spatial regions can order independently of the bulk system. In paper I, we study smeared quantum phase transitions in binary alloys A[subscript 1-x]B[subscript x] that are tuned by changing the composition x. We show that in this case the ordered phase is extended over all compositions x
Author: Vladimir Dobrosavljevic Publisher: Oxford University Press ISBN: 0199592594 Category : Science Languages : en Pages : 583
Book Description
When many particles come together how do they organize themselves? And what destroys this organization? Combining experiments and theory, this book describes intriguing quantum phases - metals, superconductors and insulators - and transitions between them. It captures the excitement and the controversies on topics at the forefront of research.
Author: Mucio Continentino Publisher: Cambridge University Press ISBN: 1107150256 Category : Science Languages : en Pages : 249
Book Description
Focusing on experimental results, this updated edition approaches the problem of quantum phase transitions from a new and unifying perspective.
Author: Chetan Vyankatesh Kotabage
Author: Chetan Vyankatesh Kotabage
Author: Fawaz Y. Hrahsheh
Author: Subir Sachdev
Author: Lincoln Carr
Author: Yurij Holovatch
Author: Manal M. Al-Ali
Author: David Nozadze
Author: J. C. Toledano
Author: Vladimir Dobrosavljevic
Author: Mucio Continentino