Wellmann Felix, Bode Nina, Wessels Peter, Overmeyer Ludger, Neumann Jörg, Willke Benno, Kracht Dietmar
Opt Express. 2021 Mar 29;29(7):10140-10149. doi: 10.1364/OE.420350.
Design studies for the next generation of interferometric gravitational wave detectors propose the use of low-noise single-frequency high power laser sources at 1064 nm. Fiber amplifiers are a promising design option because of their high output power and excellent optical beam properties. We performed filled-aperture coherent beam combining with independently amplified beams from two low-noise high-power single-frequency fiber amplifiers to further scale the available optical power. An optical power of approximately 400 W with a combining efficiency of more than 93% was achieved. The combined beam contained 370 W of linearly polarized TEM-mode and was characterized with respect to the application requirements of low relative power noise, relative beam pointing noise, and frequency noise. The noise performance of the combined beam is comparable to the single amplifier noise. This represents, to our knowledge, the highest measured power in the TEM-mode of single frequency signals that fulfills the low noise requirements of gravitational wave detectors.
下一代干涉式引力波探测器的设计研究提出使用波长为1064nm的低噪声单频高功率激光源。光纤放大器因其高输出功率和出色的光束特性而成为一种很有前景的设计选择。我们对来自两个低噪声高功率单频光纤放大器的独立放大光束进行了填充孔径相干光束合成，以进一步扩大可用光功率。实现了约400W的光功率，合成效率超过93%。合成光束包含370W的线偏振TEM模式，并根据低相对功率噪声、相对光束指向噪声和频率噪声的应用要求进行了表征。合成光束的噪声性能与单个放大器的噪声相当。据我们所知，这代表了满足引力波探测器低噪声要求的单频信号TEM模式下测得的最高功率。
