Dr
Ulrich Wahl
(Instituto Tecnologico e Nuclear ITN)
07/02/2006, 16:25
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
-...
Vitor Amaral
(Universidade de Aveiro, Portugal)
07/02/2006, 16:55
The Pr1-xCaxMnO3 displays a variety of phase transitions associated with the spin,
lattice, charge and orbital degrees of freedom [1],[2]. PrMnO3 and CaMnO3 are
antifeerromagnetic, and low doped (x<0.32) samples are ferromagnetic below Tc~130K.
For 0.32<x<0.90 the system presents a robust Charge Order state (CO) for
temperatures below TCO~150-235 K and an antiferromagnetic insulator...
A.C. Marques
(Centro de Física Nuclear da Universidade de Lisboa, Portugal)
07/02/2006, 17:15
Strontium-titanate is a perovskite ceramic material, which is of interest, e.g.,
for future devices based on metal-oxide Si heterostructures such as high-k field
effect transistors. The electrical, optical and magnetic properties of SrTiO3 can
be modified by the incorporation of dopants. For instance, transition metal doped
SrTiO3 has been considered as a candidate for a...
T. M. Mendonça
(Dep. Física, Instituto Tecnológico e Nuclear E.N. 10, P - 2686-953 Sacavém)
07/02/2006, 17:35
We present a progress report of lattice sites and collective ordering studies of
dopant oxygen atoms in HgBa2CaCu2O6.26 (Hg1212) samples with the perturbed angular
correlation technique, PAC. By measuring electric field gradients (EFG) at 199mHg
nuclei, information for characterizing the oxygen atoms, Oδ, which go to the Hg-
planes and dope the superconducting CuO2 planes with...
Frank Wagner
(Technische Physik, Universität des Saarlandes, D-66041 Saarbrücken, Germany)
07/02/2006, 17:50
Understanding and control of diffusion profiles of intrinsic and extrinsic defects in
semiconductors is of central importance for developing electronic and optoelectronic
devices. Common to all diffusion profiles in semiconductors reported so far is the
monotonously decreasing depth profile if the source of the diffusing species is
located at the surface of the crystal. In compound...
