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Suche nach „[Stirner] [Thomas]“ hat 143 Publikationen gefunden
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    Angewandte Naturwissenschaften und Wirtschaftsingenieurwesen

    Zeitschriftenartikel

    P. Harrison, W. Hagston, T. Piorek, Thomas Stirner, J. Fatah, R. Roberts, D. Ortega, A. Chesworth

    Monte Carlo simulations of carrier transport and relaxation in superlattices

    Superlattices and Microstructures, vol. 15, no. 2, pp. 209-213

    DOI: 10.1006/spmi.1994.1042

    Abstract anzeigen

    Monte Carlo simulations of carrier transport through an undoped superlattice into an extended well are described. The results illustrate clearly the important role played by LO phonons in relaxing the energy and the desirability of designing structures which minimize the need for acoustic phonon participation. Attention is drawn to the fact that although, for the standard structures investigated, the LO phonon relaxation rate is relatively independent of the miniband and/or the quantum well eigenstates, the precise shape of the form-factor for an allowed LO transition could play an important role in deciding the relative number of 'slow' carriers in an actual system.

    Angewandte Naturwissenschaften und Wirtschaftsingenieurwesen

    Zeitschriftenartikel

    P. Harrison, W. Hagston, T. Piorek, Thomas Stirner

    Boundary conditions on current carrying states and the implications for observations of Bloch oscillations

    Superlattices and Microstructures, vol. 15, no. 2, pp. 199-202

    Abstract anzeigen

    The problem of the precise form (together with the associated boundary conditions) of a one-dimensional hamiltonian describing a particle of variable mass is addressed. It is shown that although hermiticity may be a necessary condition, it is not sufficient to specify uniquely the hamiltonian. In particular one form of the latter that is widely employed in the literature is shown to lead to a violation of the Heisenberg Uncertainty Principle. However imposition of the additional demand that any singular terms arising from the kinetic energy can be transformed away does lead to a unique specification of the hamiltonian. Finally the implications of the latter with regard to the standard probability interpretation of the wavefunction and for the observation of Bloch oscillations in quantum well structures is described.

    Angewandte Naturwissenschaften und Wirtschaftsingenieurwesen

    Zeitschriftenartikel

    P. Harrison, W. Hagston, T. Piorek, Thomas Stirner, J. Fatah, R. Roberts

    Effects of interfaces and interface roughness in diluted magnetic semiconductor microstructures

    Superlattices and Microstructures, vol. 16, no. 1, pp. 11-15

    DOI: 10.1006/spmi.1994.1100

    Abstract anzeigen

    In this work a numerical model of anti-ferromagnetic spin-pairing in diluted magnetic semiconductors is used to determine the paramagnetic behaviour of both abrupt and rough interfaces. A detailed study of the paramagnetic behaviour of the individual monolayers adjacent to an abrupt interface with a non-magnetic material has not only predicted quantitatively the enhanced paramagnetism in the ultimate monolayer, it has also predicted a depressed paramagnetism in the penultimate monolayer. Furthermore, the results of the theoretical model have been compared with experimental observations in order to gain insight into intrinsic and structural properties of heterojunctions in diluted magnetic semiconductors.