Berlin 2015 – wissenschaftliches Programm
HL 95: Poster IV B (Quantum dots and wires: Prepration, characterization, optical properties, and transport)
HL 95.31: Poster
Donnerstag, 19. März 2015, 14:00–20:00, Poster B
Controlling ballistic heat conduction in a four-terminal nanoring — Christoph Kreisbeck1, •Tobias Kramer1,2, Christian Riha1, Olivio Chiatti1, Sven S. Buchholz1, Andreas D. Wieck3, Dirk Reuter3,4, and Saskia F. Fischer1 — 1Neue Materialien, Institut für Physik, Humboldt-Universität zu Berlin, 12489 Berlin, Germany — 2Mads-Clausen Institute, University of Southern Denmark, 6400 Sonderborg, Denmark — 3Angewandte Festkörperphysik, Ruhr-Universität Bochum, 44780 Bochum, Germany — 4Optoelektronische Materialien und Bauelemente, Universität Paderborn, 33098 Paderborn, Germany
The transport in a one-dimensional (1D) waveguide is dominated by the wave-like character of electrons. In simple ballistic 1D waveguides electric and thermal conductance are quantized and follow the Wiedemann-Franz law. The question is how the mode-dependent heat transfer evolves in networks of extended 1D waveguides, such as Aharonov-Bohm rings.
We show experimental data and theoretical calculations for ballistic heat transfer in a four-terminal nanodevice. By applying a gate voltage, the heat flux is distributed to different leads according to the scattering states at the wire junctions. The theoretical analysis relies on a computationally efficient wavepacket technique to model the flux through the device over a large transport window. At finite temperatures and Fermi energies we identify a strong ballistic component of the electric and heat currents, which opens the prospects to actively control the heat flux close to the quantum threshold.