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arXiv · 1104.1372

Laser-induced spin protection and switching in a specially designed magnetic dot: A theoretical investigation

G. P. Zhang·M. S. Si·T. F. George
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Abstract

Most laser-induced femtosecond magnetism investigations are done in magnetic thin films. Nanostructured magnetic dots, with their reduced dimensionality, present new opportunities for spin manipulation. Here we predict that if a magnetic dot has a dipole-forbidden transition between the lowest occupied molecular orbital (LUMO) and the highest unoccupied molecular orbital (HOMO), but a dipole-allowed transition between LUMO+1 and HOMO, electromagnetically inducedtransparency can be used to prevent ultrafast laser-induced spin momentum reduction, or spin protection. This is realized through a strong dump pulse to funnel the population into LUMO+1. If the time delay between the pump and dump pulses is longer than 60 fs, a population inversion starts and spin switching is achieved. Thesepredictions are detectable experimentally.

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G. P. Zhang, M. S. Si, T. F. George. 2011-04-07. Laser-induced spin protection and switching in a specially designed magnetic dot: A theoretical investigation. https://doi.org/10.1209/0295-5075%2F94%2F17005

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