Dresden 2020 – wissenschaftliches Programm
Die DPG-Frühjahrstagung in Dresden musste abgesagt werden! Lesen Sie mehr ...
Bereiche | Tage | Auswahl | Suche | Aktualisierungen | Downloads | Hilfe
HL: Fachverband Halbleiterphysik
HL 64: Poster II
HL 64.6: Poster
Donnerstag, 19. März 2020, 10:00–13:00, P1A
Electron pair charging in gate-defined quantum dots in indium antimonide nanowires — Felix Jekat1, Benjamin Pestka1, Sasa Gazibegovic2,3, Diana Car2,3, Sebastian Heedt3, •Marcus Liebmann1, Thomas Schäpers4, Erik Bakkers2,3, and Markus Morgenstern1 — 1II. Phys. Inst. B, RWTH Aachen Univ., Germany — 2Dept. of Appl. Phys., Eindhoven Univ., The Netherlands — 3Qutech and Kavli Inst. of Nanoscience, Delft, The Netherlands — 4PGI-9, FZ Jülich, Germany
We investigate InSb nanowires placed on bottom gates with mechanically exfoliated hexagonal boron nitride (h-BN) as a dielectric. The sample consists of five 50 nm wide finger gates with a spacing of 30 nm. The h-BN is placed on top of the finger gates. The nanowires are then placed mechanically onto h-BN. We present transport measurements on gate-defined quantum dots at temperatures down to 300 mK. Due to the dielectric, the time stability of our device improved to around 5 µeV/h. The charge stability diagram shows Coulomb diamonds with a charging energy of 2.3 meV and an orbital energy of 0.3 meV. In a perpendicular magnetic field, the zero bias state splits at around 380 mT with a doubling of the gate-periodicity below and above the transition field. This splitting resembles the one reported on nanowires partially covered by superconductors. But since in our sample there is no superconductor involved, the doubling is of unknown origin. However, the change in periodicity implies a change of the pairing mechanism, possibly triggered by electron-electron interaction.