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Injection terahertz laser using the resonant inter-layer radiative transitions in double-graphene-layer structure

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 نشر من قبل V. Ryzhii
 تاريخ النشر 2013
  مجال البحث فيزياء
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We propose and substantiate the concept of terahertz (THz) laser enabled by the resonant electron radiative transitions between graphene layers (GLs) in double-GL structures. We estimate the THz gain for TM-mode exhibiting very low Drude absorption in GLs and show that the gain can exceed the losses in metal-metal waveguides at the low end of the THz range. The spectrum of the emitted photons can be tuned by the applied voltage. A weak temperature dependence of the THz gain promotes an effective operation at room temperature.

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