Seminars Archive
Nadia Binggeli
Abstract
Monday, November 6, 2000, 17:00
Seminar Room, ground floor, Building "T"
Sincrotrone Trieste, Basovizza
Band-structure engineering at interfaces: new models for numerical experiments
Nadia Binggeli
(Institut de Physique Appliquee, Ecole Polytechnique Federale
de Lausanne)
ABSTRACT
The development of first-principles computational methods for a realistic
description of condensed matter systems has been quite dramatic in recent
years. We will present some recent applications in the fields of surface
and interfacial engineering. Our first-principles computations have probed
the microscopic mechanisms which control the local work function in nanostructured
solids, the Schottky barrier in metal/semiconductor contacts, and the band
discontinuities in semiconductor heterojunctions. The results of these
numerical experiments show the limits of currently accepted semi-empirical
models, and bring about new methods for tailoring surface and interface
parameters to a given application by means of local perturbations of structural
or chemical nature. Based on the ab initio results, new models are developed
to predict the experimental trends. Such models retain, within clearly
defined limits of applicability, the same accuracy as the first-principles
approach from which they are derived.