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Photoinduced electron transfer from organic dye molecules to semiconductor nanoparticles is the first and most important reaction step for the mechanism in the so called “wet solar cells” [1]. The time scale between the photoexcitation of the dye and the e ...
An alternative approach with respect to the standard double-slit experiment is presented to introduce the wave-like behavior of electrons. This simple and pedagogical experiment requires a commercial transmission electron microscope and a ferromagnetic fil ...
Using reflectivity and picosecond time-resolved photoluminescence, we have studied the intrinsic optical properties of negatively charged excitons in modulation doped CdTe quantum wells. In emission, we observe simultaneously a low energy exponential tail ...
The charge transport in dye-sensitized nanostructured TiO2 was studied by laser pulse induced photocurrent transients. The exptl. curves were compared to simulations using a diffusion model with an initial electron distribution of an exponential decay. The ...
We report on studies of extended defects in electron-beam-pumped Zn1-xCdxSe/ZnSe blue and blue-green laser structures. To establish a direct correlation between the local luminescence properties and the presence of structural defects, the same thin foil sa ...
We report on a novel approach to measure the phase relaxation length and femtosecond lifetime of hot quasiparticles on metal surfaces. A 4 K scanning tunneling microscope has been used to study the spatial decay of interference patterns in the local densit ...
The temperature-dependent damping of quantum-mechanical interference patterns from surface-state electrons scattering off steps on Ag(111) and Cu(111) has been studied using scanning tunneling microscopy (STM) and spectroscopy in the temperature range 3,5- ...
The interacting electron-hole system is investigated in the framework of non-equilibrium Green's functions. Using the Bethe-Salpeter equation in the ladder approximation we derive a set of equations for the polarization of the interacting electron and hole ...
A study of the elastic exciton-exciton Coulomb scattering in a semiconductor quantum well is presented, including the interexciton exchange of carriers and the spin degrees of freedom. The theoretical results show that electron-electron and hole-hole excha ...
We discuss the scheme rind test performances of this recently commissioned system in its final configuration. The tests show that the improvements in the electron optics system with respect to other instruments in the same class made it possible to reach l ...
