Showing papers in "Infrared Physics in 1980"

TL;DR: In this paper, the Burstein-Moss shift of the absorption edge was derived for the absorption constant of Pb 1− x Sn x Te (LTT) and Hg 1−x Cd x,Te (HCT) in terms of the k−p band structure parameters appropriate to the two alloy systems.

TL;DR: In this paper, a modulated visible light is used to generate thermal waves in a metal sample on one side while on the other side the emitted modulated infrared thermal radiation is detected.

TL;DR: In this article, the authors investigated the tunnel contribution to p − n junction diode electrical characteristics and showed that the soft reverse breakdown characteristic of p - n junctions in both Hg 1− x Cd x Te (HCT) and Pb 1 − x Sn x Te(LTT) is satisfactorily accounted for by the tunnel mechanism.

TL;DR: In this paper, a region of the Ge-As-Se-Te phase diagram is identified as suitable for exploitation and the potential range of optical properties of these glasses is established and measured thermal and optical data on selected glasses is presented.

TL;DR: In this paper, it was shown that the Johnson noise is a minimum at an angular frequency the reciprocal of the thermal time constant of the detecting element, and can then, for some materials, be significantly less than the background noise.

TL;DR: In this paper, three bandpass filters were constructed for use with a 0.3K bolometer and the center frequencies and bandwidths of the filters were chosen to correspond with the 1, 2 and 3 mm atmospheric windows.

TL;DR: In this paper, a capture cross section model of band to band transitions in semiconductors utilizing the Shockley-Read (S-R) lifetime recombination process is presented.

TL;DR: In this paper, the responsivity and detectivity of a pyroelectric detector pass through a maximum at low frequencies related to the detector's time constants, which can be used to calculate most of the parameters determining the detector performance.

TL;DR: In this article, a charge-coupled device action has been demonstrated for the first time in the variable bandgap alloy Hg 1−xCd x Te. 16-bit shift registers have been fabricated on 0.25 eV n -type material with a charge transfer efficiency of 0.9995.

TL;DR: In this article, a study of the various properties of liquid PbS, PbSe and PbTe is presented, and various possible models in the light of the semiconducting properties of these liquids are discussed.

TL;DR: In this article, the parameters of CdHgTe PEM far-infrared detectors were analyzed and the normalized responsivity, R v, detectivity D ∗ and time constant τ were determined, dependent on detector geometry and recombination velocities at the surface and in the volume of the sample.

TL;DR: In this paper, the atmospheric transmittance spectrum along horizontal paths up to 44 km in length was measured using a collimated radiation source and a moderate-resolution measurement system, and the results were compared with the prediction of the lowtran 4 program.

TL;DR: In this paper, a single-beam dispersive photoacoustic spectrometer system with a carbon rod source was used with a monochromator, based on a Perkin-Elmer Model 421 bed and Model 621 interchange modified to contain only 6 reflective surfaces driven by a computer-controlled step drive.

TL;DR: In this paper, a multispectral infrared photodiodes sensitive from 1-10μm have been prepared by depositing Pb Schottky barrier contacts onto layered structures of the lead salt alloy semiconductors epitaxially grown on BaF 2 substrates.

TL;DR: In this paper, the mean hemispherical emissivity in the i.m. radiation from absorbing media is calculated from published values of the components of complex index, and it is shown that the absorbance of glass has a negligible effect on the surface reflectivity except in the strong absorption band at 8-10 μm.

TL;DR: In this paper, a 1 cm3 CW CO2 capillary waveguide laser was used to fabricate a CO2 waveguide, which operates at 130 torr gas pressure, and generates 7 W of 10 μm radiation untuned and up to 3 W on individual grating-selected emission lines.

TL;DR: In far-infrared Fourier spectroscopy with a Michelson interferometer deviations in the measured transmission spectra of samples with non-negligible reflection can be observed.

TL;DR: The N2O laser has been used as infrared pump in order to obtain far-infrared emissions in ammonia as discussed by the authors, and the Stark tuning method has enabled them to obtain thirty new emissions using different pumping schemes.

TL;DR: In this paper, two simple techniques to measure the wavelengths of CW FIR lasers optically pumped by a CO2 laser in the 40-1200 μm range are presented. But these techniques use a comparison between the FIR and pump wavelengths.

TL;DR: In this article, a Martin-Puplett polarizing interferometer was used to extend the useful frequency range of a Fourier transform spectroscopy (FTS) system.

TL;DR: In this article, a polarizing Michelson interferometer for the far-infrared and millimetre regions is described, which uses a simple mechanical drive to attain high-resolution spectra with excellent frequency accuracy, as evidenced by measurements of the rotational parameters for N2O.

TL;DR: In this paper, the infrared reflectivity spectra of the red phase of HgI 2 have been measured in the wavenumber range extending from 10 to 2000 cm −1, and two polarization configurations, i.e. E parallel and E perpendicular to the C 4 -axis, have been inspected at ordinary and helium temperatures.

TL;DR: In this paper, a brief description of the experience with arsenic doped silicon detectors under low background conditions and electronics is presented, and measurements of detector responsivity and system noise as a function of frequency, temperature, bias, etc.

TL;DR: In this paper, the effect of the concentration of dopants on the product of PbTe abrupt junctions was analyzed for photovoltaic detectors at temperatures 77, 200 and 300K.

TL;DR: In this article, a study of g-r noise in Cd0.21Hg0.79Te crystals has been carried out with compensated and uncompensated n-type samples.

TL;DR: In this article, the authors describe an i.r. hygrometer which measures the absolute water vapour content in the atmosphere, which can be used with either the sun or the moon as a radiation source, and its design minimizes errors due to atmospheric aerosols.

TL;DR: In this paper, the authors investigated the intensity of ghostlines which occur in the spectrum obtained with a two-beam Fourier interferometer when the travel of its moving mirror is periodically distorted.

TL;DR: In this article, a double-beam, optically compensated, Fourier transform spectrometer was used for weak spectral features detection in a narrow line due to small amounts of gaseous NH3.

TL;DR: In this paper, it is shown that when account is taken of the attenuation of incident radiation into the bulk of a photoconductor the expressions for the quantum efficiency appropriate for use in equations for responsivity and detectivity have to be modified.