title: Tailoring the core electron density in modulation-doped core-multi-shell nanowires.
abstract: We show how a proper radial modulation of the composition of core-multi-shell nanowires (NWs) critically enhances the control of the free-carrier density in the high-mobility core with respect to core-single-shell structures, thus overcoming the technological difficulty of fine tuning the remote doping density. We calculate the electron population of the different NW layers as a function of the doping density and of several geometrical parameters by means of a self-consistent Schrödinger-Poisson approach: free carriers tend to localize in the outer shell and screen the core from the electric field of the dopants.
authors.affiliation: Department of Physics, Informatics, and Mathematics, University of Modena and Reggio Emilia, Via Campi 213/A, I-41125 Modena, Italy.
authors.forename: Fabrizio
authors.initials: F
authors.lastname: Buscemi
authors.forename: Miquel
authors.initials: M
authors.lastname: Royo
authors.forename: Guido
authors.initials: G
authors.lastname: Goldoni
authors.forename: Andrea
authors.initials: A
authors.lastname: Bertoni