BEGIN:VCALENDAR VERSION:2.0 CALSCALE:GREGORIAN PRODID:UW-Madison-Physics-Events BEGIN:VEVENT SEQUENCE:0 UID:UW-Physics-Event-4063 DTSTART:20160512T150000Z DTEND:20160512T160000Z DTSTAMP:20260419T075616Z LAST-MODIFIED:20160510T134144Z LOCATION:5310 Chamberlin Hall SUMMARY:Measurement of resistance induced by a single potassium atom o n chiral-angle known nanotubes: understanding the impact of a model sc atterer for nanoscale sensors\, R. G. Herb Condensed Matter Seminar\, Prof. Masa Ishigami\, U. Central Florida DESCRIPTION:Even atomic impurities are expected to impact device prope rties of carbon nanotubes. Such sensitivity makes them ultimately usef ul for sensor technologies. Rational design for nanotube-based sensors requires precise understanding of how impurities impact transport pro perties of nanotubes. Such impurity-induced carrier scattering is expe cted to be dependent on the chirality of nanotubes and the nature of s cattering potentials imposed by impurities. Yet until our recent measu rements\, it has been impossible to measure the impact of impurities o n resistance of carbon nanotubes with known chirality. We have develop ed arrays of experimental techniques to control experiments down to at omic scale to measure the scattering strength of charged impurities on semiconducting single-walled carbon nanotubes with known chirality. T he resistivity of nanotubes is measured as a function of the density o f adsorbed potassium atoms\, enabling the determination of the resista nce added by an individual potassium atom. Holes are scattered 37 time s more efficiently than electrons by an adsorbed potassium atom. The d etermined scattering strength is used to reveal the spatial extent and depth of the scattering potential for potassium\, a model Coulomb ads orbate\, paving way for rational design of nanotube-based sensors.
\n URL:https://www.physics.wisc.edu/events/?id=4063 END:VEVENT END:VCALENDAR