Lithuanian Journal of Physics article / Lietuvos fizikos žurnalo straipsnis

SHIFT OF THE COLLECTIVE MODE OF POLARIZED GRAPHENE ON A SUBSTRATE USING SPIN-SENSITIVE RESPONSE THEORY
Dominik Kreil, Michaela Haslhofer, and Helga M. Böhm
Institute for Theoretical Physics, Johannes Kepler University, Altenbergerstraβe 69, 4040 Linz, Austria
E-mail: dominik.kreil@jku.at
Received 7 June 2018; revised 6 July 2018; accepted 15 October 2018

The growing precision of optical and scattering experiments necessitates a better understanding of the influence of damping onto the collective mode of sheet electrons. As spin-polarized systems are of particular interest for spintronic applications, we here report spin-sensitive linear response functions of graphene, which give access to charge- and spin-density related excitations. We further calculate the reflectivity of graphene on an SiO₂ surface, a setup used in s-wave scanning near-field microscopy. Increasing the partial spin-polarization of the graphene charge carriers leads to a significant broadening and shift of the plasmon mode, due to single-particle interband transitions of the minority spin carriers. We also predict an antiresonance in the longitudinal magnetic response function, similar to that of semiconductor heterostructures.

Keywords: graphene, s-SNOM, collective modes, plasmom, reflectivity
PACS: 68.65.Pq, 05.30.Fk, 71.45.Gm, 71.45.-d, 71.10.-w, 71.10.Ca

POLIARIZUOTO GRAFENO ANT PADĖKLO KOLEKTYVINĖS MODOS POSLINKIS PAGAL SUKINIUI JAUTRAUS ATSAKO TEORIJĄ
Dominik Kreil, Michaela Haslhofer, Helga M. Böhm

Johaneso Keplerio universiteto Teorinės fizikos institutas, Lincas, Austrija

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