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Showing 1 to 20 of 34 for “"electron-electron interactions"”.
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Measurement of electron-electron interactions in one dimension with tunnelling spectroscopy
… of excitations born out of particle-particle interactions, which resemble the constituent single particles, albeit with renormalised mass. In one dimension, however, the formation of such a correlated state is unfavourable and the quasiparticles are completely absent. Instead, 1D fermions are …
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Hydrodynamic and ballistic transport in high-mobility GaAs/AlGaAs heterostructures
The understanding and study of electron transport in semiconductor systems has been the instigation behind the growth of semiconductor electronics industry which has enabled technological developments that are part of our everyday lives. However, most materials exhibit diffusive electron transport …
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Dynamic polarizability and collective modes in narrow-band electron systems
… impact of the ultranarrow Bloch bands and strong electron-electron interactions on the dynamical polarization response of these systems. Strong interactions alter the collective charge dynamics in a number of interesting ways, in particular by stiffening the frequency-momentum dispersion of …
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Superlattices and quantum spin Hall states in graphene and hexagonal boron nitride heterostructures
… which explore the quantum transport of electrons in heterostructures made from graphene and hBN. Depending on the relative alignment, or "twist", between the layers, a crystal of hBN can be either a non-perturbing substrate for the graphene, or a method to induce a band gap and …
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Experimental Study of Proton Rate Density in a Spherical Inertial Electrostatic Confinement Fusion Device
… been developed. The SIEC-TX generates x-rays by electron-electron interactions at relativistic velocity at the sphere center when the electrons are accelerated and focused by a spherical grid. The wavelength of the emitted x-rays shifts as the grid bias is changed. The C-device is a radically …
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Ground state perturbation theory for the many electron system in a static lattice: some plasmon properties of insulators
The problem of an interacting electron gas in a static lattice (an inhomogeneous electron gas) at zero temperature is treated by use of field theoretic perturbation theory. The unperturbed system is taken to be a non-interacting electron gas in a static lattice. The electron-electron interactions …
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HYDRODYNAMIC AND BALLISTIC TRANSPORT IN ULTRA-CLEAN 2D ELECTRON SYSTEMS
… in mesoscopic systems, resulting from strong electron-electron interactions. In the first part, we consider electrons are in near thermal equilibrium with each other, and for which case we calculate conductance by solving hydrodynamic equations. We do this for the Corbino and Hall bar …
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Interacting fermions : a holographic approach/
… or insulators. When they are metals, their electronic properties are usually described by Landau's Fermi liquid theory. That is, they behave more or less like a free Fermi gas, with a few modifications due to electron-electron interactions. However, there exist a few metallic materials whose …
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ΜΕΛΕΤΗ ΤΟΥ ΜΟΝΤΕΛΛΟΥ HUBBARD ΓΙΑ ΕΛΚΤΙΚΑ ΔΥΝΑΜΙΚΑ ΜΕΤΑΞΥ ΤΩΝ ΗΛΕΚΤΡΟΝΙΩΝ
… HUBBARD MODEL WITH ATTRACTIVE ON SITE INTERACTIONS BETWEEN ELECTRONS BY USING THE PERIODIC ONE- BODY SELF CONSISTENT STATIC APPROXIMATION. OUR RESULTS ARE IN GOOD AGREEMENT WITH THE EXISTENT MANY-BODY RESULTS, FOR NUMBER OF ELECTRONS PER LATTICE SITE, TAKING ALL VALUES FROM 0 TO 2. …
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Pseudospin transfer torques and the effect of disorder in semiconductor electron bilayers
… transport theory to investigate the influence of electron-electron interactions on interlayer transport in semiconductor electron bilayers in the absence of an external magnetic fi eld. We conclude that, even though spontaneous pseudospin order does not occur at zero field, interaction-enhanced …
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Novel transport regimes in graphene
… due to a rich and complex interplay between electron-disorder, electron-electron, and electron-phonon interactions. Graphene, a newly discovered carbon one-atom-thick material, has unique transport characteristics, some of which are already well understood, whereas some are being under …
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Screening and the effective fine structure constant in graphene
… in crystalline materials. The strength of electron-electron interactions in graphene is expected to be large due to the unusual dispersion relation of graphene’s electrons and its two-dimensional nature, but evidence of strong-correlation effects and non-Fermi liquid behavior remains …
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Computational Studies of Correlated Electrons in One-Dimension
… for spin-1/2 fermions and the inclusion of electron-phonon interactions in the Stochastic Series Expansion Quantum Monte Carlo method and the use of Quantum Parallel Tempering to improve the quality of the numerical data. For the extended Hubbard model at half-filling, we have confirmed the …
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Interaction effects and disorder in two-dimensional electron systems
… in the localised regime of two-dimensional electron systems (2DES) with varying disorder. Devices with dimensions of a few microns were fabricated from modulation doped GaAs/ AlGaAs heterostructures, where the strength of disorder was tuned by changing the width of the undoped spacer layer …
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Time resolved dynamics of charge density waves in solids : an uncorrelated and a correlated case
… charge modulation in a metal, induced by electron-phonon or electron-electron interaction, which breaks the translational symmetry of the underlying electron gas. The charge density wave order is ubiquitous among condensed matter systems, and its equilibrium properties have been well …
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Character of the Electronic States Near the Metal -Insulator Transition in Gallium Manganese Arsenide
The character of electronic states near the Mott-Anderson metal-insulator transition in the ferromagnetic semiconductor Ga1-xMn xAs is studied by cross sectional scanning tunneling microscopy. 200nm thick samples grown by MBE at UCSB with doping levels from 1.5%, close the metal-insulator …
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Character of the electronic states near the metal-insulator transition in Gallium Manganese Arsenide
The character of electronic states near the Mott-Anderson metal-insulator transition in the ferromagnetic semiconductor Ga1-xMnxAs is studied by cross sectional scanning tunneling microscopy. 200nm thick samples grown by MBE at UCSB with doping levels from 1.5%, close the metal-insulator …
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Correlated dynamics of quantum wires and cigar shaped atomic gases
… of the TLL ground state with the <br>usual electron ground state we are able to extract them from <br>the microscopic model's ground state energy. <br> <br>In this work we investigate the dependence of charge and spin dynamics <br>on the interactions in different manifestations of 1D Fermi …
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The phonon spectra of simple metals - higher order effects of the electron-ion interaction
… influence of the periodic ionic lattice on the electrons. These effects are calculated by expanding the phonon dynamical matrix in powers of the electron-ion interaction and truncating the series in accord with the two-umk1app approximation rather than the homogeneous response approximation. In …
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Single-layer transport measurements of bilayer 2D electron and hole systems in GaAs heterostructures
… we have studied bilayer two-dimensional (2D) electron and hole systems in GaAs. The work consists of three experimental studies, which involve low temperature magneto-transport measurements of one 2D system independent of the other, and one theoretical study. Firstly, we present a new …
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