Future ground-based gravitational-wave detectors are slated to detect black hole and neutron star collisions from the entire stellar history of the universe. To achieve the designed detector sensitivities, frequency noise from the laser source must be reduced below the level achieved in current Advanced LIGO detectors. This paper reviews the laser frequency noise suppression scheme in Advanced LIGO, and quantifies the noise coupling to the gravitational-wave readout. The laser frequency noise incident on the current Advanced LIGO detectors is $8 \times 10^{-5}~\mathrm {Hz/\sqrt {Hz}}$ at 1~kHz. Future detectors will require even lower incident frequency noise levels to ensure this technical noise source does not limit sensitivity. The frequency noise requirement for a gravitational wave detector with arm lengths of 40~km is estimated to be $7 \times 10^{-7}~\mathrm {Hz/\sqrt {Hz}}$. To reach this goal a new frequency noise suppression scheme is proposed, utilizing two input mode cleaner cavities, and the limits of this scheme are explored. Using this scheme the frequency noise requirement is met, even in pessimistic noise coupling scenarios.

中文翻译：

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下一代引力波探测器中的激光频率噪声

未来的地面引力波探测器将用于探测整个宇宙恒星历史中的黑洞和中子星碰撞。为了达到设计的探测器灵敏度，必须将激光源的频率噪声降低到当前先进 LIGO 探测器所达到的水平以下。本文回顾了 Advanced LIGO 中的激光频率噪声抑制方案，并量化了耦合到引力波读数的噪声。入射到当前 Advanced LIGO 探测器上的激光频率噪声为$8 \times 10^{-5}~\mathrm {Hz/\sqrt {Hz}}$在 1~kHz。未来的探测器将需要更低的入射频率噪声水平，以确保这种技术噪声源不会限制灵敏度。臂长为 40~km 的引力波探测器的频率噪声要求估计为$7 \times 10^{-7}~\mathrm {Hz/\sqrt {Hz}}$。为了达到这个目标，提出了一种新的频率噪声抑制方案，利用两个输入模式清洁器腔，并探索了该方案的局限性。使用此方案可满足频率噪声要求，即使在悲观噪声耦合情况下也是如此。