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arXiv · 1304.2509

Tuning the Ultrafast Spin Dynamics in Carrier-Density-Controlled Ferromagnets

Masakazu Matsubara·Alexander Schroer·Andreas Schmehl·Alexander Melville·Carsten Becher·Mauricio Trujillo Martinez·Darrell G. Schlom·Jochen Mannhart·Johann Kroha·Manfred Fiebig
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Abstract

Ultrafast strengthening or quenching of the ferromagnetic order of semiconducting Eu1-xGdxO was achieved by resonant photoexcitation. The modification of the magnetic order is established within 3 ps as revealed by optical second harmonic generation. A theoretical analysis shows that the response is determined by the interplay of chemically and optically generated carriers in a nonequilibrium scenario beyond the three-temperature model. General criteria for the design of spintronics materials with tunable ultrafast spin dynamics are given.

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Masakazu Matsubara, Alexander Schroer, Andreas Schmehl, Alexander Melville, Carsten Becher, Mauricio Trujillo Martinez, Darrell G. Schlom, Jochen Mannhart, Johann Kroha, Manfred Fiebig. 2013-11-06. Tuning the Ultrafast Spin Dynamics in Carrier-Density-Controlled Ferromagnets. https://doi.org/10.1038/ncomms7724

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