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Coherent optical control of spin-spin interaction in doped semiconductors

C. Piermarocchi·G. F. Quinteiro
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Abstract

We provide a theory of laser-induced interaction between spins localized by impurity centers in a semiconductor host. By solving exactly the problem of two localized spins interacting with one itinerant exciton, an analytical expression for the induced spin-spin interaction is given as a function of the spin separation, laser energy, and intensity. We apply the theory to shallow neutral donors (Si) and deep rare-earth magnetic impurities (Yb) in III-V semiconductors. When the photon energy approaches a resonance related to excitons bound to the impurities, the coupling between the localized spins increases, and may change from ferromagnetic to anti-ferromagnetic. This light-controlled spin interaction provides a mechanism for the quantum control of spins in semiconductors for quantum information processing; it suggests the realization of spin systems whose magnetic properties can be controlled by changing the strength and the sign of the spin-spin interaction.

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C. Piermarocchi, G. F. Quinteiro. 2004-08-10. Coherent optical control of spin-spin interaction in doped semiconductors. https://doi.org/10.1103/physrevb.70.235210

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