Three dimensional confined states in core-shell diameter modulated nanowires

摘要

Three-dimensional confined states in a GaP nanowire which partially covered by a uniform InP shell have been investigated in this paper. To this end, based on the effective mass approximation and by using the finite element method electronic energy states of the system were calculated. To attain physical insight on the numerical results, we have utilized the concept of one dimensional angular momentum dependent effective potential. Our results indicate a peculiar effect of increasing the 3D confinement of electrons in the shell which partially covered the nanowire by increasing the angular momentum. Surviving the effective potential declares that this effect arises as a consequence of contact with the semi-infinite nanowire parts of the system and, as a result, leads the bound states of higher angular momentum to lie in the energy continuum of the lower ones. On the other hand, application of external magnetic field reduces the number of 3D confined states in the core?shell region. Analysis of the reverse structure, i.e. InP nanowire which partially covered with GaP, indicates a significant increase in electronic confinement in the core?shell section with respect to the InP/GaP counterpart as a result of lower electronic effective mass of InP regarding to GaP.