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Intrinsic and extrinsic decay of edge magnetoplasmons in graphene

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 نشر من قبل Norio Kumada
 تاريخ النشر 2014
  مجال البحث فيزياء
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We investigate intrinsic and extrinsic decay of edge magnetoplasmons (EMPs) in graphene quantum Hall (QH) systems by high-frequency electronic measurements. From EMP resonances in disk shaped graphene, we show that the dispersion relation of EMPs is nonlinear due to interactions, giving rise to intrinsic decay of EMP wavepacket. We also identify extrinsic dissipation mechanisms due to interaction with localized states in bulk graphene from the decay time of EMP wavepackets. We indicate that, owing to the unique linear and gapless band structure, EMP dissipation in graphene can be lower than that in GaAs systems.

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