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arXiv · 2012.11074

Reduction of quantum noise using the quantum locking with an optical spring for gravitational wave detectors

Rika Yamada·Yutaro Enomoto·Izumi Watanabe·Koji Nagano·Yuta Michimura·Atsushi Nishizawa·Kentaro Komori·Takeo Naito·Taigen Morimoto·Shoki Iwaguchi·Tomohiro Ishikawa·Masaki Ando·Akira Furusawa·Seiji Kawamura
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Abstract

In our previous research, simulation showed that a quantum locking scheme with homodyne detection in sub-cavities is effective in surpassing the quantum noise limit for Deci-hertz Interferometer Gravitational Wave Observatory (DECIGO) in a limited frequency range. This time we have simulated an optical spring effect in the sub-cavities of the quantum locking scheme. We found that the optimized total quantum noise is reduced in a broader frequency band, compared to the case without the optical spring effect significantly improving the sensitivity of DECIGO to the primordial gravitational waves.

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Rika Yamada, Yutaro Enomoto, Izumi Watanabe, Koji Nagano, Yuta Michimura, Atsushi Nishizawa, Kentaro Komori, Takeo Naito, Taigen Morimoto, Shoki Iwaguchi, Tomohiro Ishikawa, Masaki Ando, Akira Furusawa, Seiji Kawamura. 2020-12-21. Reduction of quantum noise using the quantum locking with an optical spring for gravitational wave detectors. https://doi.org/10.1016/j.physleta.2021.127365

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