title: Spatially resolved ballistic optoelectronic transport measured by quantized photocurrent spectroscopy.
abstract: GaAs-based quantum point contacts (QPCs) are exploited to spatially resolve and analyze the ballistic, nonequilibrium flow of photogenerated electrons in a nanoscale circuit. Electron-hole pairs are photogenerated in a two-dimensional electron gas (2DEG), and the resulting current through an adjacent QPC is measured as a function of the laser spot position. The transmission of photogenerated electrons through the QPC is governed by the energy dispersion and the quantized momentum values of the electron modes in the QPC.
authors.affiliation: Fakultät für Physik and Center for NanoScience, Ludwig-Maximilians-Universität, Geschwister-Scholl-Platz 1, D-80539 München, Germany.
authors.forename: Klaus-Dieter
authors.initials: KD
authors.lastname: Hof
authors.forename: Franz J
authors.initials: FJ
authors.lastname: Kaiser
authors.forename: Markus
authors.initials: M
authors.lastname: Stallhofer
authors.forename: Dieter
authors.initials: D
authors.lastname: Schuh
authors.forename: Werner
authors.initials: W
authors.lastname: Wegscheider
authors.forename: Peter
authors.initials: P
authors.lastname: Hänggi
authors.forename: Sigmund
authors.initials: S
authors.lastname: Kohler
authors.forename: Jörg P
authors.initials: JP
authors.lastname: Kotthaus
authors.forename: Alexander W
authors.initials: AW
authors.lastname: Holleitner