Displacement-noise-free interferometeric gravitational-wave detector using unidirectional neutrons with four speeds

• Published in: Physics letters. A 2023-01, Vol.458, p.128581, Article 128581
• Main Authors: Iwaguchi, Shoki, Nishizawa, Atsushi, Chen, Yanbei, Kawasaki, Yuki, Ishikawa, Tomohiro, Kitaguchi, Masaaki, Yamagata, Yutaka, Wu, Bin, Shimizu, Ryuma, Umemura, Kurumi, Tsuji, Kenji, Shimizu, Hirohiko, Michimura, Yuta, Kawamura, Seiji
• Format: Article
• Language: English
• Subjects: Displacement-noise free interferometer; Gravitational wave; Mach-Zehnder interferometer; Neutron interferometer
• ISSN: 0375-9601; 1873-2429
• DOI: 10.1016/j.physleta.2022.128581

For further gravitational wave (GW) detections, it is significant to invent a technique to reduce all kinds of mirror displacement noise dominant at low frequencies for ground-based detectors. The neutron displacement-noise-free interferometer (DFI) is one of the tools to reduce all the mirror displacement noise at lower frequencies. In this paper, we describe a further simplified configuration of a neutron DFI in terms of neutron incidence direction. In the new configuration, neutrons enter the interferometer with unidirectional incidence at four speeds as opposed to two bidirectional incidences of opposite directions at two speeds as reported previously. This simplification of the neutron DFI is significant for proof-of-principle experiments. •DFI stands for displacement-noise-free interferometer.•A neutron DFI detects low-frequency gravitational waves without displacement noises.•A simplified detector configuration has unidirectional incidence at four speeds.•The four speeds are constrained to realize a neutron DFI.•This simplified configuration has a sensitivity comparable with the original one.