It has been found that MBE-deposition of (GaMn)As at intermediate substrate temperatures (around 350 °C) results in formation of nanowires (1,2). While the growth mechanism is not explored in detail, it is known from TEM studies that each wire is terminated with a Mn-rich particle. The purpose of the present work is to characterize the electronic properties of the wires, with focus on the Mn 3d states. Applying a combination of different synchrotron radiation based techniques (PES, XAS and XES) and comparing spectra from Mn in the (GaMn)As and MnAs with those from the nanowires, we have come to the conclusion that the Mn 3d states in the nanowires are clearly less hybridised than those in bulk. The XAS spectra indicate that the Mn atoms are in tetragonal coordination, as in (GaMn)As, but in a significantly stronger crystal field (3).
1. F. Martelli et al., Nano Letters 6, 2130 (2006)
2. J. Sadowski et al., to be published
3. G. van der Laan and I.W. Kirkman, J. Phys. Condens. Matter 4, 4189 (1992)
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