Optical diagnostics of laser-produced plasmas

Abstract

Laser-produced plasmas (LPPs) engulf exotic and complex conditions ranging in temperature, density, pressure, magnetic and electric fields, charge states, charged particle kinetics, and gas-phase reactions, based on the irradiation conditions, target geometries, and the background cover gas. The application potential of the LPP is so diverse that it generates considerable interest for both basic and applied research areas. Although most of the traditional characterization techniques developed for other plasma sources can be used to characterize the LPPs, care must be taken to interpret the results because of their small size, transient nature, and inhomogeneities. The existence of the large spatiotemporal density and temperature gradients often necessitates non-uniform weighted averaging over distance and time. Among the various plasma characterization tools, optical-based diagnostic tools play a key role in the accurate measurements of LPP parameters. The optical toolbox contains optical probing methods (Thomson scattering, shadowgraphy, Schlieren, interferometry, velocimetry, and deflectometry), optical spectroscopy (emission, absorption, and fluorescence), and passive and active imaging. Each technique is useful for measuring a specific property, and its use is limited to a certain time span during the LPP evolution because of the sensitivity issues related to the selected measuring tool. Therefore, multiple diagnostic tools are essential for a comprehensive insight into the entire plasma behavior. In recent times, the improvements in performance in the lasers and detector systems expanded the capability of the aforementioned passive and active diagnostics tools. This review provides an overview of optical diagnostic tools frequently employed for the characterization of the LPPs and emphasizes techniques, associated assumptions, and challenges.

arXiv comment44 pages, 31 figures

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Cited by in corpus (8)

• Review On Laser Induced Breakdown spectroscopy: Methodology and Technical Developments
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• Characterization of electron density and ionization of a uranium laser produced plasma using laser absorption spectroscopy
• Hybrid optical sensor for combined thermal and dimensional monitoring in laser processing
• Anomalous time of flight behavior of fast ions in laser produced aluminum plasma
• Imaging atomic scattering potential in centroidal diffraction of elastic electrons
• Electron density structure measurements with scattered intense laser beam
• A Comprehensive Study on the Line Profiles and Stark Widths of Ionic Transitions from Laser Produced Aluminum Plasma