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arXiv · 1103.4256

Tracking defect-induced ferromagnetism in GaN:Gd

Martin Roever·Joerg Malindretos·Amilcar Bedoya-Pinto·Angela Rizzi·Christian Rauch·Filip Tuomisto
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Abstract

We report on the magnetic properties of GaN:Gd layers grown by molecular beam epitaxy (MBE). A poor reproducibility with respect to the magnetic properties is found in these samples. Our results show strong indications that defects with a concentration of the order of 10^19 cm^-3 might play an important role for the magnetic properties. Positron annihilation spectroscopy does not support the suggested connection between the ferromagnetism and the Ga vacancy in GaN:Gd. Oxygen co-doping of GaN:Gd promotes ferromagnetism at room temperature and points to a role of oxygen for mediating ferromagnetic interactions in Gd doped GaN.

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Martin Roever, Joerg Malindretos, Amilcar Bedoya-Pinto, Angela Rizzi, Christian Rauch, Filip Tuomisto. 2011-03-22. Tracking defect-induced ferromagnetism in GaN:Gd. https://doi.org/10.1103/physrevb.84.081201

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