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arXiv · 1108.3193

All-optical four-state magnetization reversal in (Ga,Mn)As ferromagnetic semiconductors

M. D. Kapetanakis·P. C. Lingos·C. Piermarocchi·J. Wang·I. E. Perakis
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Abstract

Using density matrix equations of motion and a tight-binding band calculation, we predict all-optical switching between four metastable magnetic states of (III,Mn)As ferromagnets. This switching is initiated non-thermally within 100fs, during nonlinear coherent photoexcitation. For a single optical pulse, magnetization reversal is completed after $\sim$100 ps and controlled by the coherent femtosecond photoexcitation. Our predicted switching comes from magnetic nonlinearities triggered by a femtosecond magnetization tilt that is sensitive to un--adiabatic light--induced spin interactions.

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M. D. Kapetanakis, P. C. Lingos, C. Piermarocchi, J. Wang, I. E. Perakis. 2011-08-16. All-optical four-state magnetization reversal in (Ga,Mn)As ferromagnetic semiconductors. https://doi.org/10.1063/1.3634031

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