Ernesto Joselevich

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Carbon nanotubes combine a range of properties that make them well suited for use as probe tips in applications such as atomic force microscopy (AFM). Their high aspect ratio, for example, opens up the possibility of probing the deep crevices that occur in microelectronic circuits, and the small effective radius of nanotube tips significantly improves the(More)
Carbon nanotubes have unique mechanical, electronic, optical and thermal properties, which make them attractive building blocks in the field of nanotechnology. However, their organization into well-defined straight or curved geometries and arrays on surfaces remains a critical challenge for their integration into functional nanosystems. Here we show that(More)
The large-scale assembly of nanowires with controlled orientation on surfaces remains one challenge preventing their integration into practical devices. We report the vapor-liquid-solid growth of aligned, millimeter-long, horizontal GaN nanowires with controlled crystallographic orientations on different planes of sapphire. The growth directions,(More)
The large-scale integration of nanowires into practical devices is hindered by the limited ability to controllably assemble these nanoscale objects on surfaces. Following our first report on the guided growth of millimeter-long horizontal nanowires with controlled orientations, here we demonstrate the generality of the guided growth approach by extending it(More)
West, Solid State Commun. 111, 1 (1999). 6. G. Finkelstein, P. I. Glicofridis, S. H. Tessmer, R. C. Ashoori, M. R. Melloch, Phys. Rev. B 61, R16323 (2000). 7. A. L. Efros, Solid State Commun. 67, 1019 (1988); A. M. Chang, Solid State Commun. 74, 871 (1990); C. W. J. Beenakker, Phys. Rev. Lett. 64, 216 (1990); D. B. Chklovskii, B. I. Shklovskii, L. I.(More)
A new approach for vectorial growth of single-wall carbon nanotube arrays is presented. The origin of growth is defined by patterning the catalyst nanoparticles, while the direction of growth is defined by a local electric field parallel to the substrate. Statistical analysis of the nanotube angular distribution indicates that field-directed growth can(More)
A qualitative description of the electronic structure of single-wall carbon nanotubes from a chemical perspective is presented using real-space orbital representations and traditional concepts of aromaticity, orbital symmetry and frontier orbitals. This unusual view of carbon nanotubes allows us to merge the solid-state physics description of band(More)