A5103636779- Pulsars and Gravitational Waves Research
- Gamma-ray bursts and supernovae
- Geophysics and Sensor Technology
- Geophysics and Gravity Measurements
- Astrophysical Phenomena and Observations
- Cosmology and Gravitation Theories
- Seismic Waves and Analysis
- High-pressure geophysics and materials
- Astrophysics and Cosmic Phenomena
- Cold Atom Physics and Bose-Einstein Condensates
- Advanced Frequency and Time Standards
- Atomic and Subatomic Physics Research
- Dark Matter and Cosmic Phenomena
- Magnetic confinement fusion research
- Superconducting Materials and Applications
- Advanced Measurement and Metrology Techniques
- Advancements in Photolithography Techniques
- Gyrotron and Vacuum Electronics Research
- Superconducting and THz Device Technology
- Acoustic Wave Resonator Technologies
- Adaptive optics and wavefront sensing
- Laser Design and Applications
- Photonic and Optical Devices
- Particle Accelerators and Free-Electron Lasers
- Advanced Sensor Technologies Research
The University of Tokyo
2017-2024
Syracuse University
2022-2024
The Graduate University for Advanced Studies, SOKENDAI
2017-2023
National Astronomical Observatory of Japan
2017-2023
National Tsing Hua University
2021
Osaka University
1990
In this Perspective we summarize the status of technological development for large-area and low-noise substrate-transferred GaAs/AlGaAs (AlGaAs) crystalline coatings interferometric gravitational-wave (GW) detectors. These topics were originally presented in a workshop{\dag} bringing together members GW community from laser interferometer observatory (LIGO), Virgo, KAGRA collaborations, along with scientists precision optical metrology community, industry partners extensive expertise...
Upgrades to improve the sensitivity of gravitational wave detectors enable more frequent detections and precise source parameter estimation. Unlike other advanced interferometric such as Advanced LIGO Virgo, KAGRA requires a different approach for upgrade since it is only detector which employs cryogenic cooling test masses. In this paper, we describe possible upgrades with technologies focusing on bands compare impacts detection compact binary coalescences. We show that either fivefold...
KAGRA is a new gravitational wave detector which aims to begin joint observation with Advanced LIGO and Virgo from late 2019. Here, we present KAGRA's possible upgrade plans improve the sensitivity in decade ahead. Unlike other state-of-the-art detectors, requires different investigations for since it only employs cryogenic cooling of test mass mirrors. In this paper, on can be realized by changing input laser power, increasing mirror mass, injecting frequency dependent squeezed vacuum are...
Thermal noise in high-reflectivity mirror coatings is a limiting factor ground-based gravitational wave detectors. Reducing this coating thermal improves the sensitivity of detectors and enriches scientific outcome observing runs. Crystalline gallium arsenide aluminum-alloyed (referred to as AlGaAs) are promising candidates for future upgrades because their low noise. However, AlGaAs-based crystalline may be susceptible an electro-optic induced by fluctuations electric field. We investigated...
The detection of gravitational waves provides us with a deep insight into the Universe. In order to increase number detectable gravitational-wave sources, several future detectors will operate cryogenic mirrors. Recent studies, however, showed that residual gas molecules inside vacuum chamber adhere mirror surface and form molecular layer which grows time. This growing introduces an additional optical loss in can decrease detector's performance. We theoretically estimate by cryogenically...
The characteristics of the inner Galaxy remain obscured by significant dust extinction, and hence infrared surveys are useful to find young Cepheids whose distances ages can be accurately determined. A near-infrared photometric spectroscopic survey was carried out three classical were unveiled in disk, around 20 30 degrees Galactic longitude. targets feature small Galactocentric distances, 3-5 kpc, their velocities important as they may under environmental influence bar. While one has radial...
Ground-based laser interferometric gravitational wave detectors consist of complex multiple optical cavity systems. An arm-length stabilization (ALS) system has played an important role in bringing such detector into operational state and enhance the duty cycle. The sensitivity these can be improved if thermal noise their test mass mirror coatings is reduced. Crystalline AlGaAs are a promising candidate for this. However, traditional ALS with frequency-doubled 532 nm light no longer option...
Ground-based laser interferometric gravitational wave detectors (GWDs) consist of multiple optical cavity systems whose lengths need to be interferometrically controlled. An arm-length stabilization (ALS) system has played an important role in bringing these interferometers into operational state and enhancing their duty cycle. The sensitivity can improved if the thermal noise test mass mirror coatings is reduced. Crystalline AlGaAs are a promising candidate for this. However, current ALS...
In order to increase the number of detectable gravitational-wave sources, future detectors will operate with cryogenically cooled mirrors. However, recent studies showed that cryogenic mirrors can suffer from molecular layer formation, which introduces an additional optical loss, and detector’s performance degrades. evaluate impact on detectors, we built a folded-cavity setup developed ellipsometric measurement method. The loss induced by shows large value even at few nanometer thickness...
A triangular optical cavity is often used as a mode cleaning in precision laser interferometry such gravitational wave detectors. An alignment sensing and control system for maintaining the of with respect to incoming beam critical detector's performance. Therefore, understanding behavior angular response vital both design commissioning test system. We present linear approximation approach which not only simplifies computation but also provides comprehensive picture response. The observable...
Thermal noise in high-reflectivity mirror coatings is a limiting factor ground-based gravitational wave detectors. Reducing this coating thermal improves the sensitivity of detectors and enriches scientific outcome observing runs. Crystalline gallium arsenide aluminum-alloyed (referred to as AlGaAs) are promising candidates for future upgrades because their low noise. However, AlGaAs-based crystalline may be susceptible an electro-optic induced by fluctuations electric field. We investigated...