Physics Chat
Surface Plasmon Polariton modes in thin metallic films and graphene
Speaker: Zeeshan Ahmad. (SSOh)
Date: Friday 9 October 2020
Time: 15:00
Venue: Zoom
Surface plasmon polaritons (SPP) are collective excitations of charge density waves coupled to EM waves that can travel along a conductor-dielectric surface. Only transverse magnetic (TM) polarisation of these exists in conductor modelled by Drude conductivity. Graphene conductivity also allows transverse electric (TE) polarisation to exist. The TE SPP mode in graphene seems to have a finite lower frequency limit controlled by temperature. An upper limit is also present at twice the Fermi-level which is removed as temperature is increased from zero. The talk will give a brief derivation of graphene conductivity, present the SPP mode dispersion in graphene, and discuss the limits of frequency range at which the mode exists.