The Experts below are selected from a list of 10362 Experts worldwide ranked by ideXlab platform
S Washburn - One of the best experts on this subject based on the ideXlab platform.
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Electromechanical response of single walled carbon nanotubes to torsional strain in a self contained device
Nature Nanotechnology, 2007Co-Authors: Adam R Hall, Michael R Falvo, Richard Superfine, S WashburnAbstract:Nanoscale electronics seeks to decrease the critical dimension of devices in order to improve performance while reducing power consumption. Single-walled carbon nanotubes fit well with this strategy because, in addition to their molecular size, they demonstrate a number of unique electronic, mechanical and Electromechanical properties. In particular, theory1,2,3,4,5,6,7,8 predicts that strain can have a large Effect on the band structure of a nanotube, which, in turn, has an influence on its electron transport properties. This has been demonstrated in experiments where axial strain was applied by a scanning probe9,10,11,12. Theory also predicts that torsional strain can influence transport properties, which was observed recently in multiwalled nanotubes13. Here we present the first experimental evidence of an Electromechanical Effect from torsional strain in single-walled nanotubes, and also the first measurements of piezoresistive response in a self-contained nanotube-based nanoElectromechanical structure.
Adam R Hall - One of the best experts on this subject based on the ideXlab platform.
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Electromechanical response of single walled carbon nanotubes to torsional strain in a self contained device
Nature Nanotechnology, 2007Co-Authors: Adam R Hall, Michael R Falvo, Richard Superfine, S WashburnAbstract:Nanoscale electronics seeks to decrease the critical dimension of devices in order to improve performance while reducing power consumption. Single-walled carbon nanotubes fit well with this strategy because, in addition to their molecular size, they demonstrate a number of unique electronic, mechanical and Electromechanical properties. In particular, theory1,2,3,4,5,6,7,8 predicts that strain can have a large Effect on the band structure of a nanotube, which, in turn, has an influence on its electron transport properties. This has been demonstrated in experiments where axial strain was applied by a scanning probe9,10,11,12. Theory also predicts that torsional strain can influence transport properties, which was observed recently in multiwalled nanotubes13. Here we present the first experimental evidence of an Electromechanical Effect from torsional strain in single-walled nanotubes, and also the first measurements of piezoresistive response in a self-contained nanotube-based nanoElectromechanical structure.
Kwang J Kim - One of the best experts on this subject based on the ideXlab platform.
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solid state soft actuator exhibiting large Electromechanical Effect
Applied Physics Letters, 2002Co-Authors: Mohsen Shahinpoor, Kwang J KimAbstract:This letter deals with the discovery of large low-voltage Electromechanical actuation Effects in an electroactive polymer made with poly(ethylene oxide) and poly(ethylene glycol). The experimental observations and robust performance of the solid-state polymer actuators in the form of a strip, which is suitably surface electroded and cation doped, are reported herein. Recent laboratory discovery shows that such solid-state actuators are polymeric materials capable of exhibiting large motion actuation capabilities (>1% bending strain) in a low electric field imposed across the strip ( 10 MPa) and fast responses (>10 Hz). Moreover, a stable operation over ten millions of cycles in air is achieved with nearly no performance degradation.
V Ranjan - One of the best experts on this subject based on the ideXlab platform.
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unusual flexoelectric Effect in two dimensional noncentrosymmetric sp2 bonded crystals
Physical Review Letters, 2009Co-Authors: Ivan Naumov, A M Bratkovsky, V RanjanAbstract:We find, with the use of the first-principles calculations, that the single-atom-thick $s{p}^{2}$-bonded noncentrosymmetric crystals like boron-nitride (BN) sheet exhibit an unusual nonlinear Electromechanical Effect: they become strongly macroscopically polarized in a corrugated state (or it induces significant changes in an initially polarized state of a sheet like ${\mathrm{BC}}_{2}\mathrm{N}$). The direction of the induced polarization is in a plane of the film and depends nonanalytically on the corrugation wave vector $\mathbit{k}$. The magnitude of the polarization can reach very large values in spite of its quadratic dependence on atomic displacements due to BN sheets being able to tolerate very large mechanical strains, similar to carbon nanotubes, and this makes this general behavior of noncentrosymmetric bodies perturbed out of equilibrium quite unique. The Effect may find various applications, in particular, in a new type of nanogenerators.
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giant flexoelectric Effect in two dimensional boron nitride sheets
arXiv: Materials Science, 2008Co-Authors: Ivan Naumov, A M Bratkovsky, V RanjanAbstract:We find, with the use of first-principles calculations, that a single-atom-thick boron-nitride (BN) sheet exhibits an unusual nonlinear Electromechanical Effect: it becomes macroscopically polarized when bent out-of-plane. The direction of the induced polarization is in the plane of the film and it depends non-analitically on the corrugation wave vector k. The magnitude of the polarization can reach very high values in spite of being at least quadratic in atomic displacements due to BN sheets being able to tolerate large mechanical strains. The discovered Effect can find many applications, in particular, in a new type of efficient and reliable nanogenerators.
Toshikazu Takigawa - One of the best experts on this subject based on the ideXlab platform.
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large Electromechanical Effect of isotropic genesis polydomain nematic elastomers
Soft Matter, 2011Co-Authors: Tetsuya Okamoto, Kenji Urayama, Toshikazu TakigawaAbstract:We demonstrate that an isotropic-genesis polydomain nematic elastomer (I-PNE) exhibits a large strain reaching 35% as well as a polydomain-to-monodomain transition at a nominal electric-field strength of 25 MV m−1. The I-PNE has no ferroelectricity, and the maximum electrical strain observed is larger than the reported values for the ferroelectric chiral smectic elastomers. The I-PNE was obtained by cross-linking the mesogens in the high-temperature isotropic state and then by cooling the elastomer to the temperatures in the nematic state. The pronounced E-field responsivity originates from the softness regarding the director rotation specific to the isotropic-genesis polydomains.