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Title: Localization/Quasi-Delocalization Transitions and Quasi-Mobility-Edges in Shell-Doped Nanowires

Abstract

We propose a novel concept, namely, shell-doping of nanowires, for control of carrier mobility in nanowires. Different from traditional doping, where dopant atoms are distributed uniformly inside nanowires, shell-doping spatially confines dopant atoms within a few atomic layers in the shell region of a nanowire. Our numerical results based on the Anderson model of electronic disorder show that electrons in a shell-doped nanowire exhibit a peculiar behavior very different from that of uniformly doped nanowires. Beyond some critical doping, electron dynamics in a shell-doped nanowire undergoes a localization/quasi-delocalization transition, namely, the electron diffusion length decreases in the regime of weak disorder but increases in the regime of strong disorder. This transition is a result of the existence of quasi-mobility-edges in the energy spectrum of the system, which can be exploited experimentally through control of electron concentration, carrier density, and degree of disorder.

Authors:
 [1];  [1]
  1. ORNL
Publication Date:
Research Org.:
Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Center for Computational Sciences
Sponsoring Org.:
USDOE Laboratory Directed Research and Development (LDRD) Program; USDOE Office of Science (SC)
OSTI Identifier:
989546
DOE Contract Number:
DE-AC05-00OR22725
Resource Type:
Journal Article
Resource Relation:
Journal Name: Nano Letters; Journal Volume: 6; Journal Issue: 1
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; 77 NANOSCIENCE AND NANOTECHNOLOGY; QUANTUM WIRES; DOPED MATERIALS; CARRIER DENSITY; CARRIER MOBILITY; DIFFUSION LENGTH; ELECTRONIC STRUCTURE; MATHEMATICAL MODELS; PHASE TRANSFORMATIONS; nanowire; transport; doping

Citation Formats

Zhong, Jianxin, and Stocks, George Malcolm. Localization/Quasi-Delocalization Transitions and Quasi-Mobility-Edges in Shell-Doped Nanowires. United States: N. p., 2006. Web. doi:10.1021/nl051981m.
Zhong, Jianxin, & Stocks, George Malcolm. Localization/Quasi-Delocalization Transitions and Quasi-Mobility-Edges in Shell-Doped Nanowires. United States. doi:10.1021/nl051981m.
Zhong, Jianxin, and Stocks, George Malcolm. Sun . "Localization/Quasi-Delocalization Transitions and Quasi-Mobility-Edges in Shell-Doped Nanowires". United States. doi:10.1021/nl051981m.
@article{osti_989546,
title = {Localization/Quasi-Delocalization Transitions and Quasi-Mobility-Edges in Shell-Doped Nanowires},
author = {Zhong, Jianxin and Stocks, George Malcolm},
abstractNote = {We propose a novel concept, namely, shell-doping of nanowires, for control of carrier mobility in nanowires. Different from traditional doping, where dopant atoms are distributed uniformly inside nanowires, shell-doping spatially confines dopant atoms within a few atomic layers in the shell region of a nanowire. Our numerical results based on the Anderson model of electronic disorder show that electrons in a shell-doped nanowire exhibit a peculiar behavior very different from that of uniformly doped nanowires. Beyond some critical doping, electron dynamics in a shell-doped nanowire undergoes a localization/quasi-delocalization transition, namely, the electron diffusion length decreases in the regime of weak disorder but increases in the regime of strong disorder. This transition is a result of the existence of quasi-mobility-edges in the energy spectrum of the system, which can be exploited experimentally through control of electron concentration, carrier density, and degree of disorder.},
doi = {10.1021/nl051981m},
journal = {Nano Letters},
number = 1,
volume = 6,
place = {United States},
year = {Sun Jan 01 00:00:00 EST 2006},
month = {Sun Jan 01 00:00:00 EST 2006}
}
  • No abstract prepared.
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