Sökning: "fermi gas"

Visar resultat 1 - 5 av 6 uppsatser innehållade orden fermi gas.

1. 1. Mathematical modeling and analysis of hot carrier solar cells

   Kandidat-uppsats, Lunds universitet/Matematisk fysik; Lunds universitet/Fysiska institutionen

   Författare :Benjamin van Dijk; [2023]
   Nyckelord :solar cell; nanowires; hot carrier; nanowire; analysis; mathematical model; trends; fermi function; reservoirs; Physics and Astronomy;

   Sammanfattning : This thesis focuses on the analysis of a mathematical model of a nanowire based hot carrier solar cell. The relevance of the topic comes from the energy crisis society is facing today. Firstly, we discuss the basic principle of hot carrier solar cells and discuss several energy loss factors. LÄS MER

3. 2. Magnetic field design for polarised neutrons in European Spallation Neutron Source instruments

   Kandidat-uppsats, Lunds universitet/Kärnfysik; Lunds universitet/Fysiska institutionen

   Författare :Andrea Monzani; [2021]
   Nyckelord :FEM; COMSOL; uniform magnetic field; neutron scattering; European Spallation Source; neutron adiabaticity; neutron spin filtering; neutron spin transport; 3He polarisation analyser; Halbach coils; tetracoil; instrument design; neutron diffractometer; nuclear physics; material science; physics simulation; Physics and Astronomy;

   Sammanfattning : The goal of this project is the design of the magnetic field of the neutron analyser for the European Spallation Source instrument DREAM (Diffraction Resolved by Energy and Angle Measurements). This instrument is a neutron diffractometer and its purpose is the determination of the magnetic and chemical structure of materials. LÄS MER

4. 3. Investigating the GW self-energy of the homogeneous electron gas in real space

   Master-uppsats, Lunds universitet/Matematisk fysik; Lunds universitet/Fysiska institutionen

   Författare :Zhen Zhao; [2018]
   Nyckelord :GW method; self energy; screened-exchange; Coulomb-hole; Physics and Astronomy;

   Sammanfattning : The real space behavior of the GW self-energy in the electron gas model was investigated in this thesis work. The self-energy is naturally decomposed into the screened-exchange and the Coulomb-hole components. LÄS MER

5. 4. Quantized Transmission in an Asymmetrically Biased Quantum Point Contact

   Master-uppsats, Linköpings universitet/Teoretisk Fysik

   Författare :Erik Johansson; [2016]
   Nyckelord :;

   Sammanfattning : In this project work we have studied how a two-dimensional electron gas (2DEG) in a GaAs/AlGaAs semiconductor heterostructure can be locally confined down to a narrow bottleneck constriction called a quantum point contact (QPC) and form an artificial quantum wire using a split-gate technique by application of negative bias voltages. The electron transport through the QPC and how asymmetric loading of bias voltages affects the nature of quantized conductance were studied. LÄS MER

7. 5. A mean-field approach to attractive few-body Fermi gas

   Master-uppsats, Lunds universitet/Fysiska institutionen; Lunds universitet/Matematisk fysik

   Författare :Morten Piibeleht; [2016]
   Nyckelord :HFB; hartree-fock-bogoliubov; fermi gas; higgs mode; QRPA; quasiparticles; random phase approximation; Physics and Astronomy;

   Sammanfattning : Quantum many-body systems can be studied theoretically from first principles using microscopic models, but the computational cost of numerically exact calculations increases exponentially with the number of particles and the complexity of the interaction, limiting the systems that can be analysed. The Hartree-Fock-Bogoliubov (HFB) and quasiparticle random phase approximation (QRPA) methods, heavily used in nuclear physics, rely on mean-field approximations but scale more favourably with increasing system size and complexity. LÄS MER