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arXiv · 1501.07112

Observation of the symmetry of core states of a single Fe impurity in GaAs

J. Bocquel·V. R. Kortan·R. P. Campion·B. L. Gallagher·M. E. Flatté·P. M. Koenraad
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Abstract

We report the direct observation of two mid-gap core d-states of differing symmetry for a single Fe atom embedded in GaAs. These states are distinguished by the strength of their hybridization with the surrounding host electronic structure. The mid-gap state of Fe that does not hybridize via sigma-bonding is strongly localized to the Fe atom, whereas the other, which does, is extended and comparable in size to other acceptor states. Tight-binding calculations of these mid-gap states agree with the spatial structure of the measured wave functions, and illustrate that such measurements can determine the degree of hybridization via pi-bonding of impurity d-states. These single-dopant mid-gap states with strong d-character, which are intrinsically spin-orbit-entangled, provide an opportunity for probing and manipulating local magnetism and may be of use for high-speed electrical control of single spins.

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J. Bocquel, V. R. Kortan, R. P. Campion, B. L. Gallagher, M. E. Flatté, P. M. Koenraad. 2015-01-28. Observation of the symmetry of core states of a single Fe impurity in GaAs. https://doi.org/10.1103/physrevb.96.075207

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