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تسجيل مستخدم جديدCarrier drift velocity and edge magnetoplasmons in graphene
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We investigate electron dynamics at the graphene edge by studying the propagation of collective edge magnetoplasmon (EMP) excitations. By timing the travel of narrow wave-packets on picosecond time scales around exfoliated samples, we find chiral propagation with low attenuation at a velocity which is quantized on Hall plateaus. We extract the carrier drift contribution from the EMP propagation and find it to be slightly less than the Fermi velocity, as expected for an abrupt edge. We also extract the characteristic length for Coulomb interaction at the edge and find it to be smaller than for soft, depletion edge systems.
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We have observed propagation of Edge Magneto-Plasmon (EMP) modes in graphene in the Quantum Hall regime by performing picosecond time of flight measurements between narrow contacts on the perimeter of micrometric exfoliated graphene. We find the prop
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