Figure 2
Comparison of the SPR in protected and non-protected copper films.
(a) SPR ellipsometric reflection Ψ for a fresh unprotected sample as a function of wavelength (tan(Ψ)exp(iΔ) = rp/rs, where rp and rs are reflection coefficients for p- and s-polarizations, respectively). The thickness of the copper film was 43.5 nm. (b) p-polarized intensity reflection Rp for the same sample as a function of wavelength. (c, d) Same measurements as in (a) and (b), respectively, after 30 days. The inset in (c) emphasizes the degradation of the SPR with time. (e, f) Same as the above but for graphene-protected Cu and half a year. The inset in (e) shows the stability of graphene protected SPR with time.
