Optimal alignment sensing of a readout mode cleaner cavity.
Optimal alignment sensing of a readout mode cleaner cavity.
复制标题
读出模式清洁腔的最佳对准传感。
DOI：
10.1364/ol.36.004365
复制
发表时间：
2011
期刊：
影响因子：
3.6
通讯作者：
N. Mavalvala
中科院分区：
文献类型：
--
作者：
N. Smith;S. Ballmer;Matt Evans;Sam Waldman;K. Kawabe;Valery Frolov;N. Mavalvala
临界耦合谐振光学腔通常用作光学系统中的模式清洁器，以提高被编码为激光束的幅度调制的信号的信噪比(SNR)。要获得最佳SNR，需要保持模式清洁器相对于其上编码信号的激光光束的对准。通常，主要对波束的载波场分量敏感的自动对准系统不会提供最佳的SNR。我们提出了一种改进传统抖动对准感知的方法，在信号场上应用大幅度调制，从而产生对信号边带场对准敏感的误差信号。当与对准致动器一起使用时，这种方法可以提高检测到的信噪比；我们展示了激光干涉仪引力波天文台千米尺度探测器的信噪比提高了3倍。这种方法可以推广到其他类型的对准传感器。
Critically coupled resonant optical cavities are often used as mode cleaners in optical systems to improve the signal-to-noise ratio (SNR) of a signal that is encoded as an amplitude modulation of a laser beam. Achieving the best SNR requires maintaining the alignment of the mode cleaner relative to the laser beam on which the signal is encoded. An automatic alignment system that is primarily sensitive to the carrier field component of the beam will not, in general, provide optimal SNR. We present an approach that modifies traditional dither alignment sensing by applying a large amplitude modulation on the signal field, thereby producing error signals that are sensitive to the signal sideband field alignment. When used in conjunction with alignment actuators, this approach can improve the detected SNR; we demonstrate a factor of 3 improvement in the SNR of a kilometer-scale detector of the Laser Interferometer Gravitational-Wave Observatory. This approach can be generalized to other types of alignment sensors.