Linear and nonlinear surface polaritons in graphene-based structures
DIPC Seminars
- Speaker
-
Yuliy Bludov (Center for Physics, University of Minho, Portugal)
- When
-
2015/03/26
13:00 - Place
- Donostia International Physics Center (DIPC). Paseo Manuel de Lardizabal, 4, Donostia
- Add to calendar
- iCal
**Linear and nonlinear surface polaritons in graphene-based structures
**
Yuliy Bludov
Center for Physics, University of Minho, Portugal
It is shown, that unique property of graphene – an ability to control its
doping (and conductivity) through the external electrostatic gating – opens
a possibility to tune dynamically the dispersion properties of surface
plasmon-polaritons in graphene and control their excitation both in the
attenuated total reflection (ATR) and in periodical diffraction grating
schemes. In particular, graphene layer deposited on substrate with
periodically modulated thickness or dielectric constant demonstrates band-gap
structure of the spectrum, where positions of gap and band edges can be
effectively tuned by external gate voltage. Also by adjusting the external
gate voltage of ATR structure with graphene layer, it is possible to tune the
reflectance of the incident electromagnetic wave from total absorption to
total reflection, as well as the polarization of reflected wave.
We also demonstrate that nonlinear dielectric, covered with graphene, can
support and stabilize nonlinear transverse electric (TE) plasmon polaritons.
We demonstrate that these nonlinear TE modes have a
subwavelength localization in the direction perpendicular to the surface, with
the intensity much higher than that of an incident wave which excites the
polariton. We also demonstrate that nonlinear graphene multilayer stack is
described by discrete nonlinear Schrödinger equation, and they can support
stable discrete TM- polarized plasmon solitons.