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The effect of perpendicular electric field on Temperature-induced plasmon excitations for intrinsic silicene

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 نشر من قبل Jhao-Ying Wu
 تاريخ النشر 2015
  مجال البحث فيزياء
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We use the tight-binding model and the random-phase approximation to investigate the intrinsic plasmon in silicene. At finite temperatures, an undamped plasmon is generated from the interplay between the intraband and the interband-gap transitions. The extent of the plasmon existence range in terms of momentum and temperature, which is dependent on the size of single-particle-excitation gap, is further tuned by applying a perpendicular electric field. The plasmon becomes damped in the interband-excitation region. A low damped zone is created by the field-induced spin split. The field-dependent plasmon spectrum shows a strong tunability in plasmon intensity and spectral bandwidth. This could make silicene a very suitable candidate for plasmonic applications.

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