Place: Kleiner Physik-Hörsaal, Geschwister-Scholl-Platz
Time: 15:30 h
Absolute Negative Resistance in a Two Dimensional Electron Gas
Ismet Inonu Kaya
Sabanci University, Istanbul, Turkey
Ballistic conductors as well as Drude conductors are restricted to have positive three terminal resistances. Intercarrier scattering does not exist in the former transport regime while it does not play a role in the conductivity of the latter. However, in a ballistic device when the energy of the electrons is elevated, these scattering events start to dominate the transport properties. A three-terminal device fabricated on a two dimensional electron gas displays an unusual potential depression at the middle contact, yielding absolute negative resistance. Hot carriers conveyed between two electrostatic barriers yields both current transfer ratios that far exceed unity. The observed reversal of the current or potential in the middle terminal is interpreted as the quantum analog of the classical Bernoulli's effect.