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Updated: Jul 7, 2026

Construction and Characterization of External Cavity Diode Lasers for Atomic Physics
Published on: April 24, 2014
Measurement of the linewidth of a continuous-wave laser with a cavity-length modulation technique
1Department of Physics, Korea Advanced Institute of Science and Technology, 373-1 Kusong-dong, Yusong, Taejon 305-701, Korea. jwkim@kriss.re.kr
Abstract:
We introduce a Fabry-Perot cavity-length modulation technique for measuring the linewidth of a continuous wave (cw) laser. We calculate the peak intensity of a cw laser transmitted through a Fabry-Perot cavity as a function of mirror speed. By fitting the experimental data to the results of the calculation, we determine the linewidth of a frequency-stabilized cw laser. The linewidth of a cw ring dye laser measured in the 570-590-nm wavelength range is approximately 170 +/- 20 kHz. We also demonstrate the use of this technique to measure the reflectivity of a high-reflectance mirror.

