Speaker
Dr
Ulrich Wahl
(Instituto Tecnologico e Nuclear ITN)
Description
Solid state physics at ISOLDE aims at the study of the structural, electrical,
optical, magnetic and transport properties related to impurities in a variety of
technologically and fundamentally relevant materials, including semiconductors,
metals, high-Tc superconductors and ceramic oxides.
This talk will give an overview on the recent ISOLDE activities in this field,
including
- lattice location of dopants and impurities in wide band gap semiconductors by
means of emission channeling,
- identification of the chemical identity of optical centers in semiconductors using
photoluminescence studies of radioactive impurities,
- characterization of deep levels in semiconductors using radioactive Deep Level
Transient Spectroscopy (DLTS),
- study of the structural and magnetic properties of Fe in semiconductors by means
of the Moessbauer effect,
- configuration of excess O and F dopants in Hg-based High-Tc superconductors,
- probing of charge ordering effects in phase transitions of colossal magneto-
resistive oxides,
- understanding of magnetic hyperfine fields at impurities on metal surfaces and
within the bulk obtained by means of perturbed angular correlation (PAC).
An outlook on experiments planned for the near future will be given as well.
Author
Dr
Ulrich Wahl
(Instituto Tecnologico e Nuclear ITN)
