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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 ...
Semiconductor quantum wires (QWRs) are promising structures for optoelectronics applications, since they can provide quantum confinement for charge carriers in two dimensions. The advantage that they offer over conventional quantum wells (QWs) is due to th ...
In highly excited semiconductor systems near the transition from direct to indirect band structure (cross-over) the energetic distance between different conduction band minima is a nonmonotonous function of the excitation intensity. A theoretical explanati ...
We present a study of the electronic properties of In(x)Ga1-xAs/GaAs quantum wells when grown on vicinal substrates, based on photoluminescence (PL) and PL excitation experiments under high magnetic field. The samples measured have a wide range of In conte ...
By means of Raman and photoluminescence measurements we have studied the effect of strain and confinement on the optical phonon spectrum of single InAs quantum wells. The frequency region of longitudinal optical phonons confined in both the InAs well and I ...
Evidence of tunneling and electronic coupling in a one-dimensional system is reported. This is accomplished by comparing low-temperature photoluminescence and photoluminescence excitation spectra of GaAs double quantum wires of different barrier widths wit ...
The temperature and excitation intensity dependencies of the photoluminescence (PL) spectra of GaAs/Al0.3Ga0.7As superlattices (SL's) having randomly distributed well widths are studied. Our results indicate that the electronic properties of disordered SL' ...
When a growth interruption is applied to the top interface of a nominally 3 monolayers (ML) thick InAs quantum well (QW), grown on an InP substrate, the InAs layer relaxes by formation of three-dimensional (3D) islands. The emission from the QW is split in ...
We report evidence of a large blue shift (up to 70 meV) in the photoluminescence spectra of InAs/InP island like quantum wells following the reduction of the InP top barrier layer thickness from 6 nm to near zero. The photoluminescence intensity only start ...
We report on microscopic photoluminescence and photoluminescence excitation of thin Al0.3Ga0.7As/GaAs quantum wells grown on exactly oriented (001) GaAs substrates. The experiments are done at low temperature by selectively exciting a few mu m(2) of the sa ...
