Determination of average refractive index of spin-coated DCG films for HOE fabrication

The determination of optical constants (i.e., real and imaginary parts of the complex refractive index (nc) and thickness (d)) of ultrathin films is often required in photonics. It may be done by using, for example, surface plasmon resonance (SPR) spectroscopy combined with either profilometry or atomic force microscopy (AFM). SPR yields the optical thickness (i.e., the product of nc and d) of the film, while profilometry and AFM yield its thickness, thereby allowing for the separate determination of nc and d. In this paper, we use SPR and profilometry to determine the complex refractive index of very thin (i.e., 58 nm) films of dye-doped polymers at different dye/polymer concentrations (a feature which constitutes the originality of this work), and we compare the SPR results with those obtained by using spectroscopic ellipsometry measurements performed on the same samples. To determine the optical properties of our film samples by ellipsometry, we used, for the theoretical fits to experimental data, Bruggeman’s effective medium model for the dye/polymer, assumed as a composite material, and the Lorentz model for dye absorption. We found an excellent agreement between the results obtained by SPR and ellipsometry, confirming that SPR is appropriate for measuring the optical properties of very thin coatings at a single light frequency, given that it is simpler in operation and data analysis than spectroscopic ellipsometry.

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Determination of pseudo-refractive index in self-assembled ligand layers from spectral shift of surface plasmon resonances in colloidal silver nanoplates

Zeitschrift für Physikalische Chemie ◽

10.1515/zpch-2020-1786 ◽

2021 ◽

Vol 0 (0) ◽

Author(s):

Pavel Malakhovsky ◽

Dmitry Murausky ◽

Dmitry Guzatov ◽

Sergey Gaponenko ◽

Mikhail Artemyev

Keyword(s):

Refractive Index ◽

Surface Plasmon ◽

Mie Theory ◽

Spectral Shift ◽

Localized Surface Plasmon ◽

Clear Trend ◽

Silver Nanoplates ◽

Assembled Monolayers ◽

Self Assembled

Abstract We examined systematically how self-assembled monolayers (SAMs) of different mercaptoacids affect the spectral shift of the localized surface plasmon resonance in silver nanoplates and nanospheres. We observed a clear trend in the magnitude of a redshift with a molecular length or the SAM thickness within a homologous series of aliphatic mercaptoacids: the thicker shell the stronger the red shift. Using classic Mie theory for plasmonic core-dielectric shell spheres and oblate spheroids we developed the method for determination of a pseudo-refractive index in SAM of different molecules and obtained a good correlation with the reference refractive indices for bulk long-chain aliphatic acids, but only in case of silver nanoplates. Calculations for silver core–shell nanospheres gave overestimated values of refractive index perhaps due to restrictions of Mie theory on the minimum particle size.

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Determination of non-linear refractive index of laser crystals and ceramics via different optical techniques

Optical Materials X ◽

10.1016/j.omx.2020.100065 ◽

2020 ◽

Vol 8 ◽

pp. 100065

Author(s):

Laurent Lamaignère ◽

Guido Toci ◽

Barbara Patrizi ◽

Matteo Vannini ◽

Angela Pirri ◽

...

Keyword(s):

Refractive Index ◽

Optical Techniques ◽

Linear Refractive Index ◽

Non Linear ◽

Laser Crystals

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Determination of thermo-optic coefficient, refractive index, optical dispersion and group velocity parameters of an organic thin film

Physica B Condensed Matter ◽

10.1016/j.physb.2007.01.017 ◽

2007 ◽

Vol 393 (1-2) ◽

pp. 304-309 ◽

Cited By ~ 23

Author(s):

F. Yakuphanoglu ◽

M. Arslan

Keyword(s):

Thin Film ◽

Refractive Index ◽

Group Velocity ◽

Organic Thin Film ◽

Optical Dispersion

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Determination of Total Carbohydrates in Wine and Wine-Like Beverages by HPLC with a Refractive Index Detector: First Action 2013.12

Journal of AOAC International ◽

10.5740/jaoacint.13-320 ◽

2014 ◽

Vol 97 (2) ◽

pp. 498-505 ◽

Cited By ~ 2

Author(s):

Steve Kupina ◽

Mark Roman ◽

D Anderson ◽

S Bhandari ◽

M S Cardozo ◽

...

Keyword(s):

Refractive Index ◽

Reference Material ◽

Organic Acids ◽

Red Wine ◽

Collaborative Study ◽

Ion Exchange Resin ◽

White Wine ◽

Negative Control ◽

Total Carbohydrates

Abstract An international collaborative study was conducted of an HPLC-refractive index (RI) detector method for the determination of the combined amounts of sugars, glycerol, organic acids, and phenolic compounds in wines and wine-like beverages. Nine collaboratinglaboratories representing major winery, contract laboratories, and government laboratories tested eight different materials as blind duplicates using the proposed method. Sample materials included red and white wines, port, wine cooler, and nonalcoholic wine. One material was a negative control, and one material was a reference material. Samples were either treated with an ion-exchange resin to remove interferingorganic acids prior to analysis or left untreated toinclude organic acids and phenolics. Red wine samples were treated with polyvinylpolypyrrolidone to remove potential interferences from phenolics prior to analysis. The HPLC analyses were performed on a Bio-Rad Fast Acid Analysis Column using RI detection. Reproducibility (RSDR) for untreated samples(sugars + phenolics + organic acids) ranged from 6.6% for Titrivin AA4 reference material to 11.0% for dry red wine. RSDR for treated samples (sugars only) ranged from 6.8% for white zinfandel to 18.9% for dry white wine. RSDR for treatedsamples (sugars only) + glycerol ranged from 6.4% for white zinfandel to 19.8% for dry red wine. Based on these results, the method was adopted as Official First Action status for determination of total carbohydrates in wine and wine-like beverages.

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