Dresden 2006 – wissenschaftliches Programm
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HL: Halbleiterphysik
HL 42: Quantum dots and wires: Preparation and characterization I
HL 42.8: Vortrag
Donnerstag, 30. März 2006, 12:45–13:00, POT 51
Magnetic Properties of Vanadium-doped ZnO-nanorods — •Eva Schlenker1, Augustin Che Mofor1, Bianca Postels1, Marc Kreye1, Andrey Bakin1, Andreas Waag1, Carsten Ronning2, Joachim Lüdke3, Volker Janke3, Sibylle Sievers3, and Martin Albrecht3 — 1Institut für Halbleitertechnik, Technische Universität Braunschweig, Braunschweig, Germany — 2II. Physikalisches Institut, Georg-August-Universität Göttingen, Göttingen, Germany — 3Physikalisch-Technische Bundesanstalt (PTB), Braunschweig, Germany
There has been much focus on the properties of the wide-bandgap semiconductor ZnO, not only for opto- but also for magneto-electronic applications. According to theoretical predictions, ZnO doped with transition metals is a promising candidate to exhibit ferromagnetism with a Curie temperature exceeding 300 K.
We report on our results concerning ZnO-nanorods grown by aqueous chemical growth and vapour phase epitaxy. The samples have been implanted with V ions, reaching concentrations up to 1.8 at.%. Photoluminescence (PL) measurements performed after the implantation process reveal a severely defective material. Subsequent annealing at 600 ∘C leads to a structural recovery of the matrix and therefore restores the original PL intensity. In order to clarify if the ZnVO-nanorods show ferromagnetism, we carried out Magnetic Force Microscopy (MFM) and Superconducting Quantum Interference Device (SQUID) measurements. The MFM measurements were performed either with or without application of an external magnetic field, both on ensembles as well as on single detached rods. The scans clearly display a magnetic contrast.