Faraday-effect polarimeter-interferometer system for current density measurement on EAST

Journal Article · Sat Nov 15 00:00:00 EST 2014 · Review of Scientific Instruments

DOI:https://doi.org/10.1063/1.4889777· OSTI ID:22303826

Liu, H. Q.; Zou, Z. Y.; Li, W. M.; Wang, Z. X.; Qian, J. P.; Yang, Y.; Zeng, L.; Wei, X. C.; Hu, L. Q.; Wan, B. N. ^[1]; Ding, W. X.; Brower, D. L. ^[2]; Lan, T.; Li, G. S. ^[1]

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1. Institute of Plasma Physics, Chinese Academy of Sciences, Hefei, Anhui 230031 (China)
2. Department of Physics and Astronomy, University of California Los Angeles, Los Angeles, California 90095 (United States)

A multichannel far-infrared laser-based POlarimeter-INTerferometer (POINT) system utilizing the three-wave technique is under development for current density and electron density profile measurements in the EAST tokamak. Novel molybdenum retro-reflectors are mounted in the inside wall for the double-pass optical arrangement. A Digital Phase Detector with 250 kHz bandwidth, which will provide real-time Faraday rotation angle and density phase shift output, have been developed for use on the POINT system. Initial calibration indicates the electron line-integrated density resolution is less than 5 × 10{sup 16} m{sup −2} (∼2°), and the Faraday rotation angle rms phase noise is <0.1°.

• OSTI ID: 22303826
• Journal Information: Review of Scientific Instruments, Vol. 85, Issue 11; Other Information: (c) 2014 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA); ISSN 0034-6748
• Country of Publication: United States
• Language: English

Related Subjects

46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND TECHNOLOGY
70 PLASMA PHYSICS AND FUSION TECHNOLOGY
CALIBRATION
CURRENT DENSITY
ELECTRON DENSITY
FARADAY EFFECT
HT-7U TOKAMAK
INTERFEROMETERS
LASERS
MOLYBDENUM
PHASE SHIFT
POLARIMETERS
RESOLUTION