Densidade de máximos da condutância em nanofios

Abstract

Universal fluctuations are one of the most important characteristics to detect chaos in quantum scattering processes, these are presented in terms of the correlation function which measures the degree of coherence in a chaotic system. The degree of coherence is related to the breadth of coherence length, which defines the form of the correlation function. A simple process to obtain the coherence length, proposed in the area of nuclear physics, is based on the counting of the maxima of the cross section as a function of the energy. This method was recently inserted in the area of mesoscopic physics. The authors show analytically that it is possible to obtain the correlation length by counting the maxima of the conductance curve as a function of the load energy and the magnetic field perpendicular or parallel to the device. This fact shows that the method is a viable alternative in nanodevices to obtain the correlation length instead of directly using the correlation function which in general requires many realizations to be generated. However, this method has not been tested in any type of nanodevices from the point of view of the tight-binding and experimental model. In this work we present a complete study on the universal fluctuations of conductance from the tight-binding model to a nearly one-dimensional nanowire subjected to a perpendicular and parallel magnetic field. Finally, we used this method for the first time in experimental data of magnetoconductance of an InAs nanowire subjected to magnetic fields perpendicular and parallel.