arosa_2020 ========== Y\. Arosa and R\. de la Fuente, "Refractive index spectroscopy and material dispersion in fused silica glass", Opt\. Lett\. 45, 4268 \(2020\) `Source record `__ · :doc:`Catalogue ` · :doc:`Review register ` DOI: `10\.1364/ol\.395510 `__ **Source kind:** measurement **Recorded technique:** White\-light spectral interferometry \('refractive index spectroscopy by broadband interferometry', RISBI\)\: the sample in one arm of a Michelson interferometer, three spectrometers \(UV\-Vis 260\-480 nm, Vis 400\-1000 nm, NIR 900\-1700 nm; bandwidths in Fig\. 2\), the phase ambiguity resolved with an Abbe refractometer at the sodium D line \(589\.3 nm\), the arm difference L from a further spectral interferogram \(pp\. 4268\-4269\)\. The refractive index \(RI\) comes from the unwrapped phase, Eq\. \(5\); the group index \(GI\) independently, from the local period of the fringes, Eq\. \(6\)\. Sample\: a UV\-grade fused silica plate made by Newport Corporation, 20 mm diameter, 2\.0593 \+\- 0\.0005 mm thick \(micrometer\)\. **Materials in structured entries:** SiO2 **Dataset quantities:** None recorded. **Contents:** 0 datasets; 1 formula. Curation notes -------------- Pages 4268\-4271 are pdf pages 1\-4\. Identity checked against the first page\. WHAT IS HERE\. The measured RI and GI are shown only as differences from fits \(Fig\. 3\) and from Malitson \(Fig\. 4\); the dispersion parameter D and its difference from Malitson's in Fig\. 5 \(figures only, not digitised\)\. No tabulated n\. Temperature not stated\. 'The accuracy achieved using our device is approximately 0\.0002 in RI units' \(p\. 4269, citing their earlier work\); 'our experimental resolution \(2 x 10^\-4\)' against Malitson's 1e\-6 \(p\. 4270\)\. FITS \(p\. 4269\-4270\)\. Three three\-term Sellmeier fits\: Fit1 to the RI alone \(rms 6\.6e\-6 from the measured RI, but a GI far from the measured one at long wavelengths\); Fit2 to the GI alone; Fit3 to RI and GI together \(maximum differences 1\.4e\-4 in RI and 3\.7e\-4 in GI, rms 2\.7e\-5 and 9\.2e\-5\)\. Only Fit3's coefficients are printed \(Table 1\)\. Against Malitson's formula over 260\-1700 nm the paper states maximum differences 1\.1e\-4 \(RI\) and 7\.4e\-4 \(GI\), rms 7\.2e\-5 and 3\.0e\-4; zero\-dispersion wavelength 1\.277 um for Fit3, 'approximately 6 nm greater than the reference value' \(p\. 4270\)\. TABLE 1 \(image checked\)\. Also prints Malitson's coefficients rounded to four digits \(0\.6962, 0\.4079, 0\.8975; 0\.068, 0\.116, 9\.896 um\)\: a reproduction of malitson\_1965/sellmeier, not recorded as a formula \(the rounded poles change n by up to 4e\-4 over 260\-1700 nm\)\. COMPARISON\. The refractiveindex\.info page SiO2/Arosa \(formula 1, 0\.26\-1\.7 um, coefficients 0\.9310, 0\.079, 0\.1735, 0\.130, 2\.1121, 14\.918\) is Table 1's Fit3 exactly\. **Recorded bibliographic identity status:** VALIDATED\_WITH\_WARNINGS. This concerns identification of the source; it does not establish the scientific correctness of its contents. Datasets -------- No datasets are recorded. Formulas -------- arosa\_2020/sellmeier\_fit3 ~~~~~~~~~~~~~~~~~~~~~~~~~~~ .. code-block:: text { "id": "sellmeier_fit3", "form": "n2_sellmeier", "terms": { "B": [ "0.9310", "0.1735", "2.1121" ], "C": [ "0.006241", "0.016900", "222.546724" ] }, "range_nm": [ 260.0, 1700.0 ], "material": "SiO2", "equation": "Eq. (7) with Table 1 ('Present study'), p. 4270", "printed": "n^2(lambda) = 1 + c1 lambda^2/(lambda^2 - lambda1^2) + c2 lambda^2/(lambda^2 - lambda2^2) + c3 lambda^2/(lambda^2 - lambda3^2); C1 = 0.9310, C2 = 0.1735, C3 = 2.1121, lambda1 = 0.079, lambda2 = 0.130, lambda3 = 14.918 (um)", "variable": "lambda: wavelength in um (the medium is not stated)", "range": "260-1700 nm (the measured range); fitted to the measured RI and GI together (Fit3)", "coefficients": { "C1": "0.9310", "C2": "0.1735", "C3": "2.1121", "lambda1": "0.079", "lambda2": "0.130", "lambda3": "14.918" }, "check": "With the printed (rounded) coefficients: zero-dispersion wavelength 1.2775 um (printed 1.277 um), 4.7 nm above Malitson's Eq. (1) (printed 'approximately 6 nm'); against Malitson over 260-1700 nm, maximum RI difference 2.6e-4 (at 260 nm; printed 1.1e-4) and rms 5.2e-5 (printed 7.2e-5), GI maximum 1.3e-3 (printed 7.4e-4). Not reproduced at the ultraviolet end: lambda1 and lambda2 are printed to two or three significant digits, which is enough to shift n there by 1e-4. Checked 2026-09-26." } The terms C are the squares of the printed lambda\_i \(0\.079^2 = 0\.006241, 0\.130^2 = 0\.016900, 14\.918^2 = 222\.546724\)\. The authors' preferred fit \('the dispersion equation resulting from Fit3 was the one that best accounted for the material dispersion in FS', p\. 4270\)\. Sample\: Newport UV\-grade fused silica; temperature not stated\. Corrections ----------- No dataset errata are recorded in this source record. Formula corrections, where recorded, appear with their formulas above. Curation notes may also discuss corrections or unresolved interpretation. Consult the :doc:`review register ` for the checks and decisions.