Figure 2.

Absorption coefficient (colored lines) as a function of photon energy. Solid lines are for α₁(ℏω). Dashed lines are for , and dotted lines are for α(ℏω,I) = α₁(ℏω) + α₃(ℏω,I). The results are for R₁ = 10 nm, L = 20 nm, P = 0, F = 0, and I = 2×10⁴W/cm². Several values of the outer radius have been considered.