Determination of the spectral-dependent refractive index of a single layer in a natural multilayer system: comparison of different approaches

MARINA INCHAUSSANDAGUE; DEMETRIO MACÍAS; DIANA SKIGIN; ALEXANDRE VIAL

APPLIED OPTICS

OPTICAL SOC AMER

Lugar: Washington; Año: 2017 vol. 56 p. 1807 - 1816

0003-6935

By means of heuristic optimization techniques, we estimate the unknown refractive index of one layer of a periodicnatural multilayer system from far-field reflectance data. To take into account the dispersive characteristics ofthe material, we employ two different strategies. The first is based on the retrieval of Lorentz model-relatedparameters, to describe the unknown dielectric permittivity within a specific spectral range. The second strategy,based on a wavelength-by-wavelength approach, takes into account the reflectance values for each wavelength ata time. Through some examples, we compare the performance of both strategies when they look for the bestestimates and analyze the error involved in each case. The applicability of both approaches to the case of noisyreflectance spectra is also explored.