Dresden 2003 – wissenschaftliches Programm
Bereiche | Tage | Auswahl | Suche | Downloads | Hilfe
HL: Halbleiterphysik
HL 34: Transporteigenschaften
HL 34.1: Vortrag
Mittwoch, 26. März 2003, 16:45–17:00, POT/81
Tuning the dimension of an electron gas embedded in gated free-standing nanostructures — •E. M. Höhberger1, D. Schröer1, R. H. Blick1, J. P. Kotthaus1, W. Wegscheider2, M. Bichler3, and D. Schuh3 — 1Center for NanoScience & Sektion Physik, LMU München, 80539 München — 2Institut für Angewandte und Experimentelle Physik, Universität Regensburg, 93040 Regensburg — 3Walter-Schottky-Institut, TU München, 85747 Garching
Freely suspended nanostructures with a thickness in the range of 100 nm only permit a discrete spectrum of lattice vibrations in the restricted dimension leading to characteristic modes of high excitation probability. Such phonon cavities can be realized in a GaAs/AlGaAs heterostructure by electron lithography and a subsequent combination of dry and wet etching techniques. Integration of a low-dimensional electron system within the free-standing cavity allows to investigate the modified electron-phonon interaction in transport measurements. Furthermore, equally suspended gate electrodes crossing the cavity permit continuous tuning of the electronic system. In particular, the dimensionality of the initially two-dimensional electron gas can be reduced to one (quantum point contact) and finally zero dimensions (single or double quantum dot) by successive depletion of several gate electrodes, thus enabling a detailed analysis of the electron-phonon interaction in the phonon cavity.