Correlation-Induced Phase Transitions in Two-Dimensional Electron Systems - read free eBook in online reader or directly download on the web page. Select files or add your book in reader. Download and read online ebook Correlation-Induced Phase Transitions in Two-Dimensional Electron Systems write by A. Isihara. This book was released on 1982. Correlation-Induced Phase Transitions in Two-Dimensional Electron Systems available in PDF, EPUB and Kindle. The electrons in inversion or accumulation layers of MOSFETs or in semiconductor-semiconductor interfaces show prominent many-body effects. A new theory off the correlation energy is developed for these electrons such that the results are applicable to a wide density range. The ground-state energy is obtained for all densities. It is continuous and convergent, but changes its analytical form at r sub s = 1.414. Associated with this change is a divergence of the compressibility that occurs at r sub s =1.989. Hence, around this r sub s, the system can be considered to be in a liquidlike state. In the (001) direction of silicon inversion layers, the two valleys, occupied equally by the electrons at high densities, may be populated unevenly due to electron correlations. This unbalance will cause a valley occupancy phase transition at r sub s =8.011, in close agreement with a recent experiment. Under a magnetic field, the susceptibility is enhanced nonlinearly when the density of electrons is reduced. This enhancement becomes very strong toward r sub s =13.0, beyond which a spin-polarized state is favored.
Phases and Phase Transitions of Strongly Correlated Electron Systems
Phases and Phase Transitions of Strongly Correlated Electron Systems - read free eBook in online reader or directly download on the web page. Select files or add your book in reader. Download and read online ebook Phases and Phase Transitions of Strongly Correlated Electron Systems write by Pouyan Ghaemi Mohammadi. This book was released on 2008. Phases and Phase Transitions of Strongly Correlated Electron Systems available in PDF, EPUB and Kindle. Different experiments on strongly correlated materials have shown phenomena which are not consistent with our conventional understandings. We still do not have a general framework to explain these properties. Developing such a general framework is much beyond the scope of this thesis, but here we try to address some of challenges in simpler models that are more tractable. In correlated metals it appears as strong correlations have different effect on different parts of fermi surface. Perhaps most striking example of this is normal state of optimally doped cuprates; the quasiparticle peaks on the nominal fermi surface do not appear uniformly. We try to track such phenomena in heavy fermion systems, which are correlated fermi liquids. In these systems, a lattice of localized electrons in f or d orbitals is coupled to the conduction electrons through an antiferromagnetic coupling. Singlets are formed between localized and conduction electrons. This singlet naturally have non-zero internal angular momentum. This nontrivial structure leads to anisotropic effect of strong correlations. Internal structure of Kondo singlet can also lead to quantum Hall effect in Kondo insulator, and formation of isolated points on the fermi surface with fractionalized quasiparticles. In the second part we study a phase transition in Heisenberg model between two insulating phases, Neel ordered and certain spin liquid state, popular in theories of the cuprates. The existence of such a transition has a number of interesting implications for spin liquid based approaches to the underdoped cuprates and clarifies existing ideas for incorporating antiferromagnetic long range order into such a spin liquid based approach. This transition might also be enlightening, despite fundamental differences, for the heavy fermion critical points where a second order transition between the heavy fermion phase and a metallic phase with magnetic antiferromagnetic order is observed.
Quantum Phase Transitions in Two Dimensional Electron Systems Under Strong Magnetic Field
Quantum Phase Transitions in Two Dimensional Electron Systems Under Strong Magnetic Field - read free eBook in online reader or directly download on the web page. Select files or add your book in reader. Download and read online ebook Quantum Phase Transitions in Two Dimensional Electron Systems Under Strong Magnetic Field write by Dongzi Liu. This book was released on 1994. Quantum Phase Transitions in Two Dimensional Electron Systems Under Strong Magnetic Field available in PDF, EPUB and Kindle.
Ground States of the Two-Dimensional Electron System at Half-Filling under Hydrostatic Pressure
Ground States of the Two-Dimensional Electron System at Half-Filling under Hydrostatic Pressure - read free eBook in online reader or directly download on the web page. Select files or add your book in reader. Download and read online ebook Ground States of the Two-Dimensional Electron System at Half-Filling under Hydrostatic Pressure write by Katherine A. Schreiber. This book was released on 2019-09-04. Ground States of the Two-Dimensional Electron System at Half-Filling under Hydrostatic Pressure available in PDF, EPUB and Kindle. This thesis presents the discovery of a surprising phase transition between a topological and a broken symmetry phase. Phase transitions between broken symmetry phases involve a change in symmetry and those between topological phases require a change in topological order; in rare cases, however, transitions may occur between these two broad classes of phases in which the vanishing of the topological order is accompanied by the emergence of a broken symmetry. This thesis describes observations of such a special phase transition in the two-dimensional electron gas confined in the GaAs/AlGaAs structures. When tuned by hydrostatic pressure, the ν = 5/2 and ν = 7/2 fractional quantum Hall states, believed to be prototypical non-Abelian topological phases of the Pfaffian universality class, give way to an electronic nematic phase. Remarkably, the fractional quantum Hall states involved are due to pairing of emergent particles called composite fermions. The findings reported here, therefore, provide an interesting example of competition of pairing and nematicity. This thesis provides an introduction to quantum Hall physics of the two-dimensional electron gas, contains details of the high pressure experiments, and offers a discussion of the ramifications and of the origins of the newly reported phase transition.
On the Thermodynamics at Quantum Phase Transitions in Two Dimensional Electron Systems
On the Thermodynamics at Quantum Phase Transitions in Two Dimensional Electron Systems - read free eBook in online reader or directly download on the web page. Select files or add your book in reader. Download and read online ebook On the Thermodynamics at Quantum Phase Transitions in Two Dimensional Electron Systems write by Babak Hosseinkhani. This book was released on 2004. On the Thermodynamics at Quantum Phase Transitions in Two Dimensional Electron Systems available in PDF, EPUB and Kindle.
