Plasma and Fusion Research
Volume 8, 2402063 (2013)
Regular Articles
- National Institute for Fusion Science, 322-6 Oroshi-cho, Toki 509-5292, Japan
- 1)
- Department of Quantum Matter, Hiroshima University, 1-3-1 Kagamiyama, Higashihiroshima 739-8530, Japan
- 2)
- Research Center for Development of Far-Infrared Region, University of Fukui, 3-9-1 Bunkyo, Fukui 910-8507, Japan
- 3)
- Institute of Laser Engineering, Osaka University, 2-6 Yamadaoka, Suita, Osaka 565-0871, Japan
Abstract
Terahertz wave diagnostics have been developed for current and future high-temperature and high-density fusion plasma measurements. Since the combined system of a reflectometer and a delayometer requires a wide-band frequency source for the density profile measurements, a terahertz pulse is a possible candidate. A test system using terahertz time-domain spectroscopy has been constructed to develop the diagnostics. The system utilizes a femtosecond fiber laser as a pumping source and a bow-tie-type photoconductive antenna as a THz wave emitter. An output THz pulse with a frequency of up to 2 THz has been obtained. Some investigations involving measurement of the refractive index of a test material are performed, and the transmission dispersion effects of an optical fiber are determined.
Keywords
THz-TDS, fusion plasma diagnostics, electron density, reflectometry, delayometry
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This paper may be cited as follows:
Tokihiko TOKUZAWA, Yutaka KADOYA, Masahiko TANI, Kohji YAMAMOTO, Masanori HANGYO, Hideaki KITAHARA, Kenji TANAKA, Ichihiro YAMADA and Kazuo KAWAHATA, Plasma Fusion Res. 8, 2402063 (2013).