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Resonant Landau-Zener transitions in helical magnetic fields

144   0   0.0 ( 0 )
 نشر من قبل Pawe{\\l} W\\'ojcik dr
 تاريخ النشر 2014
  مجال البحث فيزياء
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The spin-dependent electron transport has been studied in magnetic semiconductor waveguides (nanowires) in the helical magnetic field. We have shown that -- apart from the known conductance dip located at the magnetic field equal to the helical-field amplitude $B_h$ -- the additional conductance dips (with zero conductance) appear at magnetic field different from $B_h$. This effect occuring in the non-adiabatic regime is explained as resulting from the resonant Landau-Zener transitions between the spin-splitted subbands.



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