Dresden 2003 – wissenschaftliches Programm
Bereiche | Tage | Auswahl | Suche | Downloads | Hilfe
TT: Tiefe Temperaturen
TT 5: Supraleitung: Massivmaterialien, Bandleiter, Pinning, Vortexdynamik, Transporteigenschaften, Korngrenzen I
TT 5.6: Vortrag
Montag, 24. März 2003, 16:00–16:15, HSZ304
Investigation of flux flow and pinning properties in superconductor-2DEG hybrids. — •Harald Scheel1, A. R. Goñi1, C. Kristukat1, C. Thomsen1, and K. Eberl2 — 1Institut für Festkörperphysik, TU-Berlin, Berlin, Germany — 2MPI für Festkörperforschung, Stuttgart, Germany
We performed power dissipation measurements on thin superconducting Pb-films being thermally evaporated on the surface of a modulation-doped GaAs/AlGaAs heterostructure. Magnetic coupling via moving flux lines in the vortex state to the nearby two-dimensional electron gas enables us to introduce an extra viscosity for the vortices due to eddy-current generation in the 2DEG. By changing the carrier density of the 2DEG, which is achieved by applying a gate voltage between the 2DEG and a metallic back contact, it is possible to reduce the velocity of the moving flux lines, enabling us to study the flux flow dynamics in the superconducting film.
In addition, we measure the 2D electron density with photoluminescence and Shubnikov-de Haas and study its dependence on the gate voltage and its variation due to the presence of the superconductor.