Lattice mismatch in epitaxial layered heterostructures with small characteristic lengths induces large, spatially nonuniform strains. The components of the strain tensor have been shown experimentally to affect the electronic properties of semiconductor structures. Here a technique is presented for calculating the influence of strain on electronic properties. First the linear elastic strain in ...

We have used the Hartree-Fock Random Phase Approximation (HFRPA) to study the interacting electron gas in a quantum wire. The spectra of intersubband spin-flip excitations reveal a considerable red shift with respect to single-particle HF energies. That signals on appearance of collective intersubband spind-density excitations due to the exchange interaction. The long wavelength dispersions of ...

Laser-induced optical potentials for atoms have led to remarkable advances in precision measurement, quantum information and towards addressing fundamental questions in condensed-matter physics. Here, we describe analogous optical potentials for electrons in quantum wells and wires that can be generated by optically driving the transition between a single electron and a three-body electron–exci...

The lateral magnetic confinement of quasi two-dimensional excitons into wire like structures is studied. Spin effects are take into account and two different magnetic field profiles are considered, which experimentally can be created by the deposition of a ferromagnetic stripe on a semiconductor quantum well with magnetization parallel or perpendicular to the grown direction of the well. We fin...

In this thesis electronic transport through nanoscale devices is modeled by means of quantum physics. Moving from ballistic transport towards a detailed description of electron-phonon scattering, the used formalism changes from wave functions to the non-equilibrium Green’s functions (NEGF). The simulation framework consists of the quantum mechnical simulator SIMNAD, which was developed at the I...

We review recent results on the linear and non-linear optical response of realistic quantum-wire structures. Our theoretical approach is based on a set of generalized semiconductor Bloch equations, and allows a full threedimensional multisubband description of Coulomb correlation for any shape of the confinement profile, thus permitting a direct comparison with experiments for available state-o...

Si wire arrays are a promising architecture for solar-energy-harvesting applications, and may offer a mechanically flexible alternative to Si wafers for photovoltaics. To achieve competitive conversion efficiencies, the wires must absorb sunlight over a broad range of wavelengths and incidence angles, despite occupying only a modest fraction of the array's volume. Here, we show that arrays havi...

A low-dimensional system is one where the motion of microscopic degrees-of-freedom, such as electrons, phonons, or photons, is restricted from exploring the full three dimensions of our world. There has been tremendous interest in low-dimensional quantum systems during the past twenty years, fueled by a constant stream of striking discoveries and also by the potential for, and realization of, n...