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 10 of 10 for “"Quantum Monte Carlo simulations"”.
-
Quantum Monte Carlo simulations of electrons and holes
… We study systems of electrons and holes with quantum Monte Carlo (QMC) techniques, covering three related areas: (1) elastic scattering of excitons, (2) thermodynamics of electron-hole plasmas, and (3) electrons confined in a quantum dot. Excitons are bound states of an electron and a hole, …
-
Electron-ion correlation and finite-size effects in quantum Monte Carlo simulations
… of a mixture of electrons and ions using the quantum Monte Carlo method. In many electronic structure studies, purely electronic properties are calculated on a static potential energy surface generated by ``clamped'' ions. This can lead to quantitative errors, for example, in the prediction of …
-
Few- and many-body physics of dipoles in ion traps and optical lattice simulators
The presence of strong interactions in quantum many-body systems makes the analytical treatment of such systems very difficult. In this thesis we explore two possible proposals for simulating strongly correlated, quantum many-body systems: quantum simulations using trapped-ion quantum computers, …
-
Strong coupling methods for lattice QCD
… and (4) Hamiltonian formulation and Quantum Monte Carlo simulations. Most of the results were obtained via a dual formulation for lattice QCD derived from a strong coupling expansion. All results are limited to the strong coupling regime, i.e. valid on coarse lattices, where the sign …
-
Magnetic-field-induced antiferromagnetism in the Kondo lattice
… of this system on a square lattice, backed up by quantum Monte Carlo calculations, reveals an interesting separation of magnetic field scales. For Zeeman energy comparable to the Kondo energy, the spin gap closes and the system develops transverse staggered magnetic order. The charge gap, however, …
-
The BCS - BEC Crossover in Ultracold Fermion Gases
… $U(1)$ gauge symmetry which underlies both quantum condensation phenomena. Recently much attention has been paid to this problem, since Feshbach resonances allow for an experimental implementation of crossover physics in cold fermion gases. The strong interactions close to resonance call for …
-
Spin Polarization of Ground State Electron Gas at Low Densities
… structure of materials. In this work we use Quantum Monte Carlo simulations to study the spontaneous polarization of electron gas at low densities, for both two and three dimensions. Quantum Monte Carlo is a powerful method to tackle many-body Fermion problems, and its high accuracy has been …
-
Algorithms for quantum simulation: design, analysis, implementation, and application
Simulating the Hamiltonian dynamics of quantum systems is one of the most promising applications of digital quantum computers. In this dissertation, we develop an understanding of quantum simulation algorithms concerning their design, analysis, implementation, and application. We implement three …
-
Dynamics of ultracold bosons in a disordered optical lattice
… area of interest is in dynamical behavior near quantum phase boundaries, such as the generation of quench-induced excitations in the presence of disorder. Another area concerns heat flow, relaxation, and thermalization. The primary focus of this thesis is driving a gas across a disorder-induced …
-
First principles and machine learning methods in molecules, fluids, and solids
… developing an exact formalism for a quantum operator, investigating the origins of intriguing phenomena in solids using first principle methods, and heuristic data-driven machine learning to guide biomedical developments. The quantum Monte Carlo method is used to study molecules where …