Abstract: A semiconductor device that utilizes intraband photon absorption in quantum dots to provide a capacitive photodetector. The presence of the quantum dots creates confined energy states within the photodetector device. Electrons are trapped in these confined energy states. When the photodetector is illuminated by light having an appropriate photon energy, the stored electrons are released to the conduction band, causing a change in the capacitance of the photodetector. By measuring this change in capacitance, light incident on the photodetector can be detected and quantified.

Abstract: A semiconductor device that utilizes intraband photon absorption in quantum dots to provide a capacitive photodetector. The presence of the quantum dots creates confined energy states within the photodetector device. Electrons are trapped in these confined energy states. When the photodetector is illuminated by light having an appropriate photon energy, the stored electrons are released to the conduction band, causing a change in the capacitance of the photodetector. By measuring this change in capacitance, light incident on the photodetector can be detected and quantified.

Abstract: An intermediate band solar cell is provided. The intermediate band material of the intermediate band solar cell consists of a collection of quantum dots of a semiconductor material that are immersed in a volume of a second semiconductor material. The first semiconductor material has a rock salt-type crystalline structure, and the second semiconductor material has a zinc blende structure. The quantum dots are produced by the immiscibility of the first semiconductor material in the second semiconductor material. A combination of the first and second semiconductor materials with a very similar lattice constant can therefore be selected such that the layer of intermediate band material does not have mechanical stress accumulation.

Abstract: Procedure to obtain semiconductor materials with electronic levels close to the mid-bandgap (deep levels) which do not suffer from the non-radiative recombination by multiple phonon emission (MPE) associated to the existence of that kind of levels. The procedure consist in doping by any means the semiconductor with a density sufficiently high of the impurities producing the deep level, so that a Mott transition of the electron wavefunctions representing the localized states in the impurities is induced, in such a way that these wavefunctions become distributed across the whole semiconductor and are shared by all the impurities. When this happens, local charge density variations, and thus non-radiative recombination by MPE, disappear. Based on the resulting materials (semiconductors with three separate energy bands and radiative behavior (1), (2) and (3)) different optoelectronic devices can be fabricated (solar cells, photodetectors, lasers, etc.