An electrical analogy to Mie scattering - Caridad, Jose M.; Connaughton, Stephen; Ott, Christian; Weber, Heiko B.; Krstic, Vojislav (Nature Communications, 2016)
Keywords: Mie scattering is an optical phenomenon that appears when electromagnetic waves; in particular light; are elastically scattered at a spherical or cylindrical object. A transfer of this phenomenon onto electron states in ballistic graphene has been proposed theoretically; assuming a well-defined incident wave scattered by a perfectly cylindrical nanometer scaled potential; but experimental fingerprints are lacking. We present an experimental demonstration of an electrical analogue to Mie scattering by using graphene as a conductor; and circular potentials arranged in a square two-dimensional array. The tabletop experiment is carried out under seemingly unfavourable conditions of diffusive transport at roomtemperature. Nonetheless; when a canted arrangement of the array with respect to the incident current is chosen; cascaded Mie scattering results robustly in a transverse voltage. Its response on electrostatic gating and variation of potentials convincingly underscores Mie scattering as underlying mechanism. The findings presented here encourage the design of functional electronic metamaterials.