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Spatial structure of an individual Mn acceptor in GaAs

A. M. Yakunin·A. Yu. Silov·P. M. Koenraad·J. H. Wolter·W. Van Roy·J. De Boeck·J. -M. Tang·M. E. Flatte
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Abstract

The wave function of a hole bound to an individual Mn acceptor in GaAs is spatially mapped by scanning tunneling microscopy at room temperature and an anisotropic, cross-like shape is observed. The spatial structure is compared with that from an envelope-function, effective mass model, and from a tight-binding model. This demonstrates that anisotropy arising from the cubic symmetry of the GaAs crystal produces the cross-like shape for the hole wave-function. Thus the coupling between Mn dopants in GaMnAs mediated by such holes will be highly anisotropic.

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A. M. Yakunin, A. Yu. Silov, P. M. Koenraad, J. H. Wolter, W. Van Roy, J. De Boeck, J. -M. Tang, M. E. Flatte. 2004-02-01. Spatial structure of an individual Mn acceptor in GaAs. https://doi.org/10.1103/physrevlett.92.216806

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