Global ETD Search
Search theses and dissertations gathered from participating repositories worldwide. Every result links back to the library that holds it. No account is needed.
Results
Showing 1 to 11 of 11 for “"Dynamical Mean Field Theory"”.
-
The Study of Transition Metal Oxides using Dynamical Mean Field Theory
… physical phases not observed in bulk systems. Dynamical mean-field theory (DMFT) emerges as a successful numerical method to treat the strong correlation. The combination of density functional and dynamical mean-field theory (DFT+DMFT) is a prospective ab initio approach for studying realistic …
-
Cluster Dynamical Mean-Field Theory: Applications to High-Tc Cuprates and to Quantum Chemistry
In this thesis we use the recently developed dynamical mean-field approximation to study problems in strongly correlated electron systems, including high-Tc cuprate superconductors as well as a few quantum chemical reference systems. We start with an introduction to the background of the …
-
Density-Functional Theory+Dynamical Mean-Field Theory Study of the Magnetic Properties of Transition-Metal Nanostructures
In this thesis, Density Functional Theory (DFT) and Dynamical Mean-Field Theory (DMFT) approaches are applied to study the magnetic properties of transition metal nanosystems of different sizes and compositions. In particular, in order to take into account dynamical electron correlation effects …
-
Strongly Correlated Electrons on a Triangular Lattice
… energy effective theories by using perturbation theory. In chapter 3, we point out potential problems with perturbative techniques used to construct low energy theories for SCES. In chapter 4, we introduce an important class of materials, namely the cobaltates NaxCoO2 and we discuss the …
-
Anistropic phenomena in strongly correlated electron systems
… lattice Hubbard model within two-site cluster dynamical mean field theory (DMFT), at zero temperature. The "two-site" approach provides a drastically simplified but physically motivated self-consistency scheme for DMFT. This is combined for the first time with cluster DMFT, within which …
-
Electronic correlations in Lix̳ CoO₂
… properties of LixCoO2 using density functional theory (DFT) and the dynamical mean-field theory (DMFT). Three main problems are addressed. First, the influence of hybridization among the eg and oxygen orbitals is studied using DFT and a modified Hubbard model which is solved within DMFT. It has …
-
Accounting for Strong Electronic Correlation in Metalloproteins
… example of where semi-local density functional theory (DFT) --- a go-to method for computational physicists --- fails. The second challenge is that of size: as this thesis will demonstrate, we must consider large cluster models that are thousands of atoms in size, which takes us beyond the reach …
-
A photoemission study of quasiparticle excitations, electron-correlation effects and magnetization dynamics in thin magnetic systems
… is focused on the electronic, spin-dependent and dynamical properties of thin magnetic systems. Photoemission-related techniques are combined with synchrotron radiation to study the spin-dependent properties of these systems in the energy and time domains. In the first part of this thesis, the …
-
Experimental consequences of mottness in high-temperature copper-oxide superconductors
… Chapter 2 contains a discussion on Cluster Dynamical Mean Field Theory (CDMFT), the principal numerical technique to be implemented in this dissertation. Chapter 3 describes the exact low-energy theory of doped Mott insulators, which largely provides a theoretical framework to this …
-
Correlated low temperature states of YFe2Ge2 and pressure metallised NiS2
… the Brinkman-Rice scenario and predicted in dynamical mean field theory calculations. Quantum oscillations have been measured at pressures as close to the insulating phase as 33 kbar and as high as 97 kbar. In addition to providing a valuable insight into the mechanism of the Mott MIT, this …
-
First-Principles Studies of Complex Oxide Materials
This thesis uses first-principles methods to study complex oxide materials. The first part of the thesis deals with complex oxide materials that have applications as lithium-ion battery electrodes. In the second part, a new method for the calculation of vibrational properties of correlated …