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Coherent magnetization precession in ferromagnetic (Ga,Mn)As induced by picosecond acoustic pulses

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 نشر من قبل Alexey Scherbakov
 تاريخ النشر 2010
  مجال البحث فيزياء
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We show that the magnetization of a thin ferromagnetic (Ga,Mn)As layer can be modulated by picosecond acoustic pulses. In this approach a picosecond strain pulse injected into the structure induces a tilt of the magnetization vector M, followed by the precession of M around its equilibrium orientation. This effect can be understood in terms of changes in magneto-crystalline anisotropy induced by the pulse. A model where only one anisotropy constant is affected by the strain pulse provides a good description of the observed time-dependent response.



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