E. D. Palik

Interference effects in luminescence studies of thin films.

Interference effects, including multiple-beam and wide-angle, associated with luminescence from within a thin film are described. A simple geometrical model is used to calculate the s- and p-polarized luminescent light assuming electric-dipole radiation. The luminescence exhibits fringes when measured both as a function of the film thickness and as a function of the wavelength of the light. In the latter case the fringes can also show a beating effect. The model is applied to several experimental examples of cathodoluminescence in SiO(2) and an example of photoluminescence in a-Si.

A bibliography of magnetooptics of solids.

This bibliography contains many of the papers dealing with magnetooptical effects in solids. It is arranged in sections by subject matter and in chronological order within sections; the papers are alphabetized in each year by first authors last name. The information given is author, title of paper, and reference.

The Use of Polarized Infrared Radiation in Magneto-Optical Studies of Semiconductors

Infrared magneto-optical studies of semiconductors often necessitate the use and measurement of various types of polarized radiation. Several magneto-optical experiments such as cyclotron resonance, Faraday effect, Voigt effect, and magneto-plasma effects are briefly described with emphasis on the types of polarized radiation involved. The design and use of several polarizing devices which have been made to facilitate these studies are discussed.

A Soleil Compensator for the Far Infrared

A Soleil compensator has been constructed of crystal quartz for use in the far infrared region. The dispersion in the birefringence has been measured between 60 μ and 170 μ. The dispersion of the 129-cm−1 absorption band which absorbs only the ordinary ray is clearly seen. The compensator may be used to produce a 90° phase shift between two normal electric vectors for wavelengths from 60 μ to 400 μ. The compensator has been tested also from 1.5 μ to 4.0 μ in the near infrared where the dispersion of the birefringence also has been measured.

Infrared characterization of surfaces and coatings by internal-reflection spectroscopy

Some problems which arise in the characterization of surfaces and coatings by internal reflection spectroscopy are described. The ir spectra of bare CaF(2) trapezoids and of ThF(4)- and ZnSe-coated trapezoids exhibit absorption bands in the same spectral region as those of H(2)O and hydrocarbon impurities. In accord with previous investigations, it is observed that the absorptance due to water is much greater in the ThF(4) films than in the ZnSe films or on the CaF(2) surfaces. These results suggest that the water is distributed throughout the ThF(4) films, whereas for ZnSe it resides primarily on the surface. In addition, a number of interesting observations on the desorption and adsorption of water and hydrocarbons to these materials are made. The experimentally observed absorptances are analyzed on the basis of the reflectance for a threelayer system. The analysis enables reasonably quantitative values for the absorption coefficient to be determined for these thin-film coatings.

Thin-film absorption coefficients by attenuated-total-reflection spectroscopy.

The application of attenuated-total-reflection spectroscopy to the measurement of the absorption coefficient of thin films is presented. For low absorption the sensitivity of ATR is discussed in terms of the concept of an effective thickness. Both the case in which the refractive index of the film is higher and the case in which it is lower than that of the ATR trapezoid are considered. Experimental ATR data for antireflection-coating materials for laser windows is analyzed and compared with calorimetric data.

A brief survey of magnetooptics.

A brief account is given of many of the areas being studied by magnetooptic techniques today. The main effort is in solids with the spectrum being broadly covered from the uv to the rf region.