Naka Fusion Institute, National Institutes for Quantum Science and Technology, Naka, Ibaraki 311-0193, Japan.
Rev Sci Instrum. 2023 Jan 1;94(1):013502. doi: 10.1063/5.0128536.
A three-color laser interferometer consisting of three Mach-Zehnder-type, one-color laser interferometers with heterodyne detection and coaxial laser beams is demonstrated. The three-color laser interferometer is considered as three sets of a two-color laser interferometer. From the two sets of the two-color laser interferometer, the value consisting only of the noise floor can be assessed. The noise floor can be reduced by subtracting the value consisting only of the noise floor from the measurement value obtained with the other two-color laser interferometer. In the case of the three lasers with wavelengths 9.25 μm, 10.59 μm, and 532 nm, a 15% noise reduction was obtained compared to the two sets of the two-color laser interferometers contained in the three-color laser interferometer. The 100-Hz noise reduction by 53% was achieved, and the other frequency noises were equal to or less than the smallest noise achieved by the two-color laser interferometers. The 100-Hz noise floor is caused by the vibration noise, which remains because of the non-coaxiality of the three beams.
本文展示了一种由三个马赫-曾德尔型单频激光干涉仪与外差探测和同轴激光束组成的三色激光干涉仪。三色激光干涉仪被视为三组双色激光干涉仪。从两组双色激光干涉仪中，可以评估仅由噪声基底组成的值。通过从用另一个双色激光干涉仪获得的测量值中减去仅由噪声基底组成的值，可以降低噪声基底。在波长为 9.25μm、10.59μm 和 532nm 的三个激光器的情况下，与包含在三色激光干涉仪中的两组双色激光干涉仪相比，获得了 15%的噪声降低。通过 53%实现了 100Hz 的噪声降低，并且其他频率噪声等于或小于通过双色激光干涉仪获得的最小噪声。100Hz 的噪声基底是由振动噪声引起的，由于三束光的非同轴性，振动噪声仍然存在。
