Michel Querry

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Extinction coefficients k(lambda) for water at 25 degrees C were determined through a broad spectral region by manually smoothing a point by point graph of k(lambda) vs wavelength lambda that was plotted for data obtained from a review of the scientific literature on the optical constants of water. Absorption bands representing k(lambda) were postulated(More)
We designed an improved wedge shaped cell for measuring Lambert absorption coefficient spectra alpha(nu) of highly absorbent liquids. The design allows for accurate determination of the apex angle of the wedge, sealing the cell, and injection of the liquid without disassembling the cell. We measured alpha(nu) for water through the 500-12,500-cm(-1)(More)
Attenuation coefficients alpha(lambda) for collimated quasi-monochromatic radiation passing through deionized filtered water were measured throughout the 418.6-640.3-nm wavelength region by use of a split-pulse laser method, which employs reference and sample cells arranged in a geometry similar to that of a Michelson interferometer. The radiant source was(More)
Measurements of the optical constants of metals at submillimeter wavelengths are sparse. We have used a nonresonant cavity to measure, at room temperature, the angle averaged absorptance spectra P(omega) of aluminum, molybdenum, tantalum, titanium, tungsten, and iron in the 30-300-cm(-1) wavenumber region. The real part of the normalized surface impedance(More)
Near normal-incidence relative spectular reflectance was measured throughout the 0.2-32.8-microm wavelength region for three cut and polished samples of Bethany Falls limestone. Water, for which the complex refractive index is well known, was the reflectance standard. Although the visual appearances of the three samples were quite different, the relative(More)
Measurements of the optical properties, and thus the optical constants, of metals at submillimeter wavelengths are almost nonexistent. We used a nonresonant cavity to measure at ambient temperature the angle averaged absorptance spectra P(omega) of gold, nickel, and lead in the 30-300-cm(-1) wave-number region. The real part of the normalized surface(More)
Silicon nanoparticles (Si NPs) with a diameter size ranging from 4 to 8 nm were successfully fabricated. They exhibit a visible photoluminescence (PL) due to the quantum confinement effect. Chemical functionalization of these Si NPs with alkyl groups allowed to homogeneously disperse them in nonpolar liquids (NPLs). In comparison to most of literature(More)
We have used spectral reflectance and transmittance measurements combined with Kramers-Krönig analyses to obtain the real (n) and imaginary (k) parts of the complex refractive index, N = n + ik, of Bacillus subtilis spores over a wavelength interval from 0.2 to 2.5 mum. Samples were in the form of thin solid films, pressed pellets, and suspensions in water(More)