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Complex domain wall dynamics in compressively strained GaMnAs epilayers

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 نشر من قبل Liza Herrera Diez
 تاريخ النشر 2008
  مجال البحث فيزياء
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The domain wall induced reversal dynamics in compressively strained GaMnAs was studied employing the magneto-optical Kerr effect and Kerr microscopy. Due to the influence of an uniaxial part in the in-plane magnetic anisotropy (90+/-Delta) domain walls with considerably different dynamic behavior are observed. While the (90+Delta) reversal is identified to be propagation dominated with a small number of domain walls, the case of (90-Delta) reversal includes the nucleation of many domain walls. The domain wall nucleation/propagation energy for both transitions are estimated using model calculations from which we conclude that single domain devices can be achievable using the (90+Delta) mode.



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