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We report on time-resolved photoluminescence studies of charged and neutral excitons in a modulation doped GaAs quantum well under resonant excitation and high magnetic field. The radiative lifetime of the charged exciton is rather short, 60 ps at zero hel ...
We study the dynamics of the charged and neutral excitons in a modulation-doped GaAs quantum well by time-resolved photoluminescence under a resonant excitation. The radiative lifetime of the charged exciton is found to be surprisingly short, 60 ps. This t ...
A comprehensive study of: leakage conduction in Pb(ZrxTi1-x)O-3 films with Pt electrodes is carried out. The conduction properties of films prepared in different ways (sol-gel coating, metalorganic chemical vapor deposition, sputtering) were studied by usi ...
Single crystals of layered semiconductors such as WS2 and MoS2 have already proven their efficiency as active elements in photovoltaic cells. Due to their high optical absorption coefficient in the visible range, these materials could be used in the form o ...
Si- and Mg-doped GaN layers were grown on c-plane sapphire substrates by molecular beam epitaxy with NH3 as the nitrogen precursor. Their optical and electrical properties were investigated by photoluminescence experiments and Hall measurements, respective ...
Raman scattering by coupled LO phonon-plasmon modes in p-type GaN layers has been measured for different hole densities up to 3 x 10(18) cm(-3) Both axial and planar coupled modes were clearly observed. The breakdown of usual selection rules for the planar ...
We report transport measurements on single crystals of Sr2RuO4-δ, grown by the flux technique. The temperature dependence of the Hall coefficient is similar to the one measured in cuprates, and the linear resistivity persists up to ~1000 K, while the super ...
Ammonia as nitrogen precursor has been used to grow m-V nitrides by molecular beam epitaxy (MBE) on c-plane sapphire substrates. The efficiency of NH3 has been evaluated allowing the determination of the actual V/III flux ratio used during the GaN growth. ...
It is shown that the unusual scattering of the currently reported photoluminescence energy of GaInP/GaAs quantum wells (QWs) can be well accounted for by considering the combined effect of In surface segregation and As/P exchange at the interfaces. The res ...
In this work, we present a correlation between the morphological characterization of InyAl1−yAs/InxGa1−xAsheterostructures grown on InP substrates for high electron mobility transistors(HEMTs) applications as determined by transmission electron microscopy, ...