Tailoring the core electron density in modulation-doped core−multi-shell nanowires

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 dop...

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Bibliographic Details
Authors: Buscemi, Fabrizio, Royo Valls, Miquel, Goldoni, Guido, Bertoni, Andrea
Format: article
Status:Versión aceptada para publicación
Publication Date:2016
Country:España
Institution:Consejo Superior de Investigaciones Científicas (CSIC)
Repository:DIGITAL.CSIC. Repositorio Institucional del CSIC
OAI Identifier:oai:digital.csic.es:10261/148255
Online Access:http://hdl.handle.net/10261/148255
Access Level:Open access
Keyword:Core-shell nanowires
Modulation doping
Tubular 2DEG
Electrostatic screening
Description
Summary: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.