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Coherent control of magnetization precession in ferromagnetic semiconductor (Ga,Mn)As

146   0   0.0 ( 0 )
 نشر من قبل Petr Nemec
 تاريخ النشر 2008
  مجال البحث فيزياء
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We report single-color, time resolved magneto-optical measurements in ferromagnetic semiconductor (Ga,Mn)As. We demonstrate coherent optical control of the magnetization precession by applying two successive ultrashort laser pulses. The magnetic field and temperature dependent experiments reveal the collective Mn-moment nature of the oscillatory part of the time-dependent Kerr rotation, as well as contributions to the magneto-optical signal that are not connected with the magnetization dynamics.



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