Surface plasmons at composite surfaces with diffusive charges
Metal surfaces with disorder or with nanostructure modifications are studied, allowing for a localized charge layer (CL) in addition to continuous charges (CC) in the bulk, both charges having a compressional or diffusive nonlocal response. The notorious problem of "additional boundary conditions" is resolved with the help of a Boltzmann equation that involves the scattering between the two charge types. Depending on the strength of this scattering, the oscillating charges can be dominantly CC or CL; the surface plasmon (SP) resonance acquires then a relatively small linewidth, in agreement with a large set of data. With a few parameters our model describes a large variety of SP dispersions corresponding to observed data.
EPL (Europhysics Letters)
- Pub Date:
- March 2012
- Condensed Matter - Mesoscale and Nanoscale Physics;
- Physics - Optics
- 6 pages, 2 figures