Stabilization of 48-and 57-mu m CH3OD lasers for plasma diagnostics

作者：Nakayama K^*; Okajima S; Akiyama T; Tanaka K; Kawahata K

来源：Journal of Instrumentation, 2015, 10(12): C12002.

DOI：10.1088/1748-0221/10/12/C12002

• Lasers
• Plasma diagnostics - interferometry, spectroscopy and imaging

Simultaneously oscillated 48-mu m and 57-mu m CH3OD lasers pumped by a 9R(8) CO2 laser have been developed as optical sources of interferometer and polarimeter for fusion plasma diagnostics. The objective of this paper is to present a method for stabilizing the two-color far-infrared (FIR) laser outputs. A stable FIR laser requires a stable pump CO2 laser and a prevention of a back reflection from the FIR laser cavity. The frequency of the pump CO2 laser has been stabilized by an external Stark-cell modulation. The back reflection has been reduced by an optical isolator using a quarter-wave plate and an absorbing thin-film reflector. The two-color FIR laser outputs have been stabilized by controlling the cavity length. As a result of these measures, we have achieved output stabilities of +/- 1.2%/h at the 48-mu m laser and +/- 1.3%/h at the 57-mu m laser.

• 出版日期2015-12