Showing papers by "Norman S. Kopeika published in 1979"
TL;DR: Spectral effects and nonlinearities that characterize illumination of dc discharges by low-intensity light and illumination of gas cells by high-intensity lasers are described in this paper, which can be used to deepen the understanding of the low intensity EM radiation interaction with gas discharges and as a possible tool for further study of gas breakdown by highintensity lasers, including further investigation of the effective photon concept.
Abstract: Spectral effects and nonlinearities that characterize illumination of dc discharges by low‐intensity light and illumination of gas cells by high‐intensity lasers are described. The similarities suggest an analogy between both cases. This analogy can be used to deepen the understanding of the low‐intensity EM radiation interaction with gas discharges and as a possible tool for further study of gas breakdown by high‐intensity lasers, including further investigation of the ’’effective photon’’ concept.
39 citations
TL;DR: Experiments involving He-Cd and Ar laser beam interactions with an Ar discharge indicate that space charge effects generated by the incident light itself are the physical mechanism responsible for nonlinearity of response in discharge regions of excited atom concentration spatial gradients.
Abstract: Experiments involving He–Cd and Ar laser beam interactions with an Ar discharge indicate that space charge effects generated by the incident light itself are the physical mechanism responsible for nonlinearity of response in discharge regions of excited atom concentration spatial gradients. This occurs with both excited atom photoionization and optogalvanic signals. Such optically generated space charges explain the role of electrode geometry in forming effective cross sections which have been used to describe mathematically the nonlinearity. The optogalvanic effect here is greater in Townsend than in glow discharges, particularly in the cathode fall. This is advantageous because of the extremely low noise and higher responsivities of Townsend discharges.
15 citations
TL;DR: In this article, photoconductive detectors with relatively flat response to wavelengths as short as 2500 A have been fabricated in thin films of zinc phosphide deposited by the close-space-transport method on to mica substrates.
Abstract: Photoconductive detectors with relatively flat response to wavelengths as short as 2500 A have been fabricated in thin films of zinc phosphide deposited by the close-space-transport method on to mica substrates. Responsivity at 2527 A was 0.13 A/W.
7 citations