Proyectos
Noise cross-correlation and Cross Andreev Reflections efficiency in two quantum point contacts connected to a HTc superconductor
Resumen
We find the non-local shot noise (S) in nanoscopic 2-Terminal junctions NS considering different symmetries of the superconductor pair potential. We determine that the contributions to the cross shot noise are due to Crossed Andreev Reflections (CAR), Elastic Cotunneling (EC), Quasiparticles transmission (Q) and Andreev Reflections (AR). We analyze two cases; the first one when the two terminals are connected to the same voltage (symmetric) and the other one when they are connected to a voltage difference V (asymmetric). The method is applied to superconductors with symmetries s, dx2 ¿y2 , dxy and s++(+¿). We find that in the tunneling limit CAR contribute positively to the shot noise cross correlation whereas Q, AR and EC contributions are negative. Depending on the symmetry, the CAR could be the dominant process in a high efficiency of the device, where the efficiency at the tunneling limit is defined as the ratio of the cross shot noise due to CAR and the complete cross shot noise. We calculate the cross Fano factor, where Positive values in the Fano factor mean positive cross correlations dominance, whereas negative values mean negative cross correlations dominance. For symmetric voltages, in the tunneling limit, the contributions to the cross Fano factor and the efficiency are the same, so the Fano factor would be a good way to test the efficiency of a Cooper pair splitter device. For the asymmetric case, at the tunneling limit and low voltages, CAR and EC compete and the CAR dominance depends on the superconductor symmetry. By the other side, for the symmetric case, the EC contributions are zero therefore CAR are the dominant processes in the tunneling limit. For voltages higher than the gap the contributions due to Q and AR make that the cross shot noise becomes negative. These properties would allow
Convocatoria
Nombre de la convocatoria:CONVOCATORIA DEL PROGRAMA NACIONAL PARA LA VISIBILIDAD INTERNACIONAL DE LA PRODUCCIÓN ACADÉMICA MEDIANTE EL APOYO PARA TRADUCCIÓN O CORRECCIÓN DE ESTILO DE ARTÍCULOS DE INVESTIGACIÓN 2013-2015
Modalidad:Modalidad 1. Revisión de estilo o traducción de artículos completos escritos por docentes de planta de la Universidad Nacional de Colombia, los cuales vayan a ser sometidos a revistas indexadas en ISI Web Of Knowledge o Scopus del Elsevier.
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