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Title: Surface effect on resonant properties of nanowires predicted by an elastic theory for nanomaterials

Abstract

A recently developed continuum theory considering surface effect in nanomaterials is adopted to investigate the resonant properties of nanowires with different boundary conditions in the present paper. The main feature of the adopted theory is that the surface effect in nanomaterials is characterized by the surface energy density of the corresponding bulk materials and the surface relaxation parameter in nanoscale. Based on a fixed-fixed beam model and a cantilever one, the governing equation of resonant frequency for corresponding nanowires is obtained. Numerical calculation of the fundamental resonant frequency is carried out, the result of which is well consistent with the existing numerical ones. Comparing to the result predicted by the conventionally structural dynamics, the resonant frequency of a fixed-fixed nanowire is improved, while that of a cantilever nanowire is weakened due to the surface effect. Both a decreasing characteristic size (height or diameter) and an increasing aspect ratio could further enhance the varying trend of resonant properties for both kinds of nanowires. The present result should be helpful for the design of nano-devices and nanostructures related to nanowires.

Authors:
;  [1]
  1. LNM, Institute of Mechanics, Chinese Academy of Sciences, Beijing 100190 (China)
Publication Date:
OSTI Identifier:
22494650
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Applied Physics; Journal Volume: 118; Journal Issue: 4; Other Information: (c) 2015 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; ASPECT RATIO; BEAMS; BOUNDARY CONDITIONS; ELASTICITY; EQUATIONS; NANOMATERIALS; NANOWIRES; RELAXATION; SURFACE ENERGY; SURFACES

Citation Formats

Yao, Yin, and Chen, Shaohua, E-mail: chenshaohua72@hotmail.com, E-mail: shchen@LNM.imech.ac.cn. Surface effect on resonant properties of nanowires predicted by an elastic theory for nanomaterials. United States: N. p., 2015. Web. doi:10.1063/1.4927290.
Yao, Yin, & Chen, Shaohua, E-mail: chenshaohua72@hotmail.com, E-mail: shchen@LNM.imech.ac.cn. Surface effect on resonant properties of nanowires predicted by an elastic theory for nanomaterials. United States. doi:10.1063/1.4927290.
Yao, Yin, and Chen, Shaohua, E-mail: chenshaohua72@hotmail.com, E-mail: shchen@LNM.imech.ac.cn. 2015. "Surface effect on resonant properties of nanowires predicted by an elastic theory for nanomaterials". United States. doi:10.1063/1.4927290.
@article{osti_22494650,
title = {Surface effect on resonant properties of nanowires predicted by an elastic theory for nanomaterials},
author = {Yao, Yin and Chen, Shaohua, E-mail: chenshaohua72@hotmail.com, E-mail: shchen@LNM.imech.ac.cn},
abstractNote = {A recently developed continuum theory considering surface effect in nanomaterials is adopted to investigate the resonant properties of nanowires with different boundary conditions in the present paper. The main feature of the adopted theory is that the surface effect in nanomaterials is characterized by the surface energy density of the corresponding bulk materials and the surface relaxation parameter in nanoscale. Based on a fixed-fixed beam model and a cantilever one, the governing equation of resonant frequency for corresponding nanowires is obtained. Numerical calculation of the fundamental resonant frequency is carried out, the result of which is well consistent with the existing numerical ones. Comparing to the result predicted by the conventionally structural dynamics, the resonant frequency of a fixed-fixed nanowire is improved, while that of a cantilever nanowire is weakened due to the surface effect. Both a decreasing characteristic size (height or diameter) and an increasing aspect ratio could further enhance the varying trend of resonant properties for both kinds of nanowires. The present result should be helpful for the design of nano-devices and nanostructures related to nanowires.},
doi = {10.1063/1.4927290},
journal = {Journal of Applied Physics},
number = 4,
volume = 118,
place = {United States},
year = 2015,
month = 7
}
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