EM description of matter (revision)
22 Setembro 2020, 09:00 • José Manuel Rebordão
Radiation from a dipole in the near and far regimes (https://youtu.be/QK5KrYakSIU, https://youtu.be/NB2AP7jvqvA). Brief reference to near-field optics.
Dielectrics, Lorentz model and explanation of dispersion. Formal impact of the complex nature of the susceptibility. Real and imaginary parts of the permittivity, wave number and refraction index. Modelling of attenuation / absorption, Beer-Lambert law. Effect of multiple resonances, normal and anomalous dispersion. Sellmeier equations.
Metals, Effective permittivity. How general equations for dielectrics can be used also for metals if permittivity is replaced by the effective permittivity; asymptotic behaviour of metals for very high frequency. Plasma frequency. Drude model. Characteristics of the propagation constant, index of refraction and attenuation as a function of frequency. Plasmonic and forbidden bands. Explanation of the visual appearance of metals (Cu, Au, Ag). Use of metals as reflectors for frequencies smaller than plasma frequency.
Data base RefractiveIndex.Info for the optical properties of materials.
BIBLIOGRAPHY
Saleh, Fundamentals of Photonics, Ch. 5.