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CreatorTitleDescriptionSubjectDate
1 Liu, FengComputational designing of carbon nanotube electromechanical pressure sensorsWe investigate electronic transport properties of single-walled carbon nanotubes (SWNT's) under hydrostatic pressure, using first-principles quantum transport calculations aided by molecular-dynamics simulation and continuum mechanics analysis. We demonstrate a pressure-induced metal-to-semiconduc...Carbon nanotubes; Computational designing; Pressure sensors; Electronic transport2004-04
2 Liu, FengGeometric constant defining shape transitions of carbon nanotubes under pressureWe demonstrate that when a single-walled carbon nanotube is under pressure it undergoes a series of shape transitions, first transforming from a circle to an oval and then from an oval to a peanut. Most remarkably, the ratio of the area of the tube cross sections at the second transition over that ...Geometric constant; Shape transitions; Carbon nanotubes; Pressure2004-03
3 Liu, FengImpurity mediated absorption continuum in single-walled carbon nanotubesThe authors demonstrate that in single-walled carbon nanotubes, a weak impurity potential can lead to a strong above-gap absorption continuum. The total absorption is enhanced due to the intraband and indirect transitions, as well as plasmon excitations, which are forbidden in perfect nanotubes. Suc...Carbon nanotubes; SWNT; Defects; Impurities; Above-gap; Absorption continuum2007
4 Liu, FengMetal-to-semiconductor transition in squashed armchair carbon nanotubesWe investigate electronic transport properties of the squashed armchair carbon nanotubes, using tight-binding molecular dynamics and the Green's function method. We demonstrate a metal-to-semiconductor transition while squashing the nanotubes and a general mechanism for such a transition. It is the ...Squashed armchair; Carbon nanotubes; Metal-to-semiconductor transition; Electronic transport; Tight-binding molecular dynamics; Squashed nanotubes2003-04
5 Saam, BrianOptically polarized 129Xe NMR investigation of carbon nanotubesWe demonstrate the utility of optically polarized 129Xe NMR in a convection cell for measuring the surface properties of materials. In particular, we show adsorption of xenon gas on oxidatively purified single- and multiwalled carbon nanotubes. The interaction between xenon and multiwalled nanotube...Carbon nanotubes; Multiwalled nanotubes; 129Xe NMR; Gas adsorption2008-12
6 Liu, FengPressure-induced hard-to-soft transition of a single carbon nanotubeWe demonstrate a hydrostatic pressure-induced hard-to-soft transition of an isolated single wall carbon nanotube, using classical and ab initio constant-pressure molecular-dynamics simulations and continuum elastic theory analysis. At low pressure, the carbon tube is hard. Above a critical pressur...Carbon nanotubes; Hard-to-soft transition2004-10
7 Rogachev, AndreySuperconducting properties of polycrystalline Nb nanowires templated by carbon nanotubesContinuous Nb wires, 7-15 nm in diameter, have been fabricated by sputter-coating single fluorinated carbon nanotubes. Transmission electron microscopy revealed that the wires are polycrystalline, having grain sizes of about 5 nm. The critical current of wires thicker than ~12 nm is very high (107 A...Polycrystalline Nb; Carbon nanotubes; Langer-Ambegaokar-McCumber-Halperin; Phase slips2003
8 Vardeny, Zeev ValentineUltrafast spectroscopy of excitons in semiconducting carbon nanotubesUltrafast relaxation dynamics of photoexcitations in semiconducting single walled carbon nanotubes (S-NTs) were investigated using polarized pump-probe photomodulation (with 150 fs time resolution) and cw polarized photoluminescence (PL). Both annealed and unannealed NT films and D 2 0 solutions of ...Non-linear optical methods; Carbon nanotubes; ultrafast dynamics2005
9 Vardeny, Zeev ValentineUniversal properties of quasi-one-dimensional excitons in semiconducting single-walled carbon nanotubes and ∏-conjugated polymersThe nature of the primary photoexcitations in semiconducting single-walled carbon nanotubes (S-SWCNTs) is of strong current interest. We have studied the emission spectra of S-SWCNTs and two different rr-conjugated polymers in solutions and films, and have also performed ultrafast pump-probe spectr...Carbon nanotubes; pi-conjugated polymers; SWCNT; Photoexcitation; Optoelectronic properties; Quasi-one-dimensional2006
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