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Solid phase epitaxy of ferromagnetic MnAs dots on GaMnAs layers

J. Sadowski·M. Adell·J. Kanski·L. Ilver·E. Janik·E. Lusakowska·J. Z. Domagala·R. Brucas·M. Hanson
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Abstract

Formation of MnAs quantum dots in a regular ring-like distribution has been found on MBE-grown (GaMn)As surfaces after low-temperature annealing under As capping. The Mn was supplied by out-diffusing Mn interstitials from (GaMn)As. With 5 at% substitutional Mn the quantum dots appeared for (GaMn)As layers thicker than 500 A. For thinner layers the Mn-rich surfaces, presumably monolayer thick MnAs, are smooth and well-ordered (1x2), and are well suited for continued epitaxial growth.

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J. Sadowski, M. Adell, J. Kanski, L. Ilver, E. Janik, E. Lusakowska, J. Z. Domagala, R. Brucas, M. Hanson. 2005-04-04. Solid phase epitaxy of ferromagnetic MnAs dots on GaMnAs layers. https://arxiv.org/abs/cond-mat/0504074

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