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Spin wave non-reciprocity and beating in permalloy by time-resolved magneto-optical Kerr effect

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 نشر من قبل Hyunsoo Yang
 تاريخ النشر 2014
  مجال البحث فيزياء
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We have studied the propagation characteristics of spin wave modes in a permalloy stripe by time-resolved magneto-optical Kerr effect techniques. We observe a beating interference pattern in the time domain under the influence of an electrical square pulse excitation at the center of the stripe. We also probe the non-reciprocal behavior of propagating spin waves with a dependence on the external magnetic field. Spatial dependence studies show that localized edge mode spin waves have a lower frequency than spin waves in the center of the stripe, due to the varying magnetization vector across the width of the stripe.



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