Asunto(s)
Enfermedad Injerto contra Huésped , Trasplante de Células Madre Hematopoyéticas , Leucemia Mieloide Aguda , Síndromes Mielodisplásicos , Humanos , Tiotepa/uso terapéutico , Busulfano/uso terapéutico , Vidarabina/uso terapéutico , Leucemia Mieloide Aguda/terapia , Síndromes Mielodisplásicos/terapia , Acondicionamiento PretrasplanteRESUMEN
The electronic properties of Cd(1-x)Mn(x)Te/CdTe semiconductor superlattices (SLs) with high Mn concentrations (x up to 0.8) were studied by means of low and room temperature photoluminescence (PL). The samples were grown by MBE on GaAs substrates with CdTe buffers. PL allowed the investigation of the optical emission from the fundamental 11H excitonic transition, revealing the high quantum efficiency and quality of the SLs. The temperature dependence of the excitonic PL energy position and excitonic line-shape broadening were studied. An exciton-longitudinal optical phonon couple model can be used to explain the experimental results very well. Photoreflectance (PR) spectra were also performed in order to compare with the authors' photoluminescence results. The combined use of PL and PR allowed a full understanding of the electronic states and optical emission characteristics of the authors' SLs. The authors' results indicate that high quality Cd(1-x)Mn(x)Te/CdTe SLs with high Mn concentrations can be grown using MBE on GaAs substrates. The possibility to have magnetic semiconductor nanostructures opens the way to applications in the field of spintronics toward devices based on new concepts.
RESUMEN
Measurement of displacements and strains is performed by extracting with a new scanning method the information from a double-exposure hologram. A real image is formed by a conjugate reference beam that illuminates a small part of the plate defining an observation direction for each point of the object under test. Sweeping the beam across the plate, which corresponds to a variation of the viewing direction, produces a movement of the fringes on the surface of the observed object. The fringes are counted during each scanning by a detector placed at the observed point. A minimum of three scannings provides all the information required to determine the three-dimensional displacement of the point itself.
