A5087247789- Pulsars and Gravitational Waves Research
- Gamma-ray bursts and supernovae
- Geophysics and Gravity Measurements
- Astrophysical Phenomena and Observations
- Geophysics and Sensor Technology
- Cosmology and Gravitation Theories
- Seismic Waves and Analysis
- Advanced Frequency and Time Standards
- Astrophysics and Cosmic Phenomena
- Mechanical and Optical Resonators
- High-pressure geophysics and materials
- Radio Astronomy Observations and Technology
- Cold Atom Physics and Bose-Einstein Condensates
- Atomic and Subatomic Physics Research
- Statistical and numerical algorithms
- Astronomical Observations and Instrumentation
- Advanced Fiber Laser Technologies
- Advanced Measurement and Metrology Techniques
- Magnetic confinement fusion research
- Adaptive optics and wavefront sensing
- Seismology and Earthquake Studies
- Black Holes and Theoretical Physics
- Superconducting Materials and Applications
- Photonic and Optical Devices
- Inertial Sensor and Navigation
University of Birmingham
2015-2024
Vrije Universiteit Amsterdam
2021-2024
National Institute for Subatomic Physics
2022-2024
LIGO Scientific Collaboration
2011-2023
Science and Technology Facilities Council
2023
Rutherford Appleton Laboratory
2023
Université Paris Cité
2023
Laboratoire AstroParticule et Cosmologie
2023
Centre National de la Recherche Scientifique
2023
California State University, Fullerton
2023
Recent theoretical developments have highlighted the potential importance of ``optical springs'' in interferometers for gravitational wave detection as a means beating standard quantum limit. We observed an optical spring effect experimentally detuned Fabry-Perot resonator which one mirror is mounted on flexure so that it has significant response to radiation pressure. The main spring, shift mechanical resonance frequency moveable mirror, agrees well with simple model.
Abstract Monitoring of vibrational eigenmodes an elastic body excited by gravitational waves was one the first concepts proposed for detection waves. At laboratory scale, these experiments became known as resonant bar detectors developed Joseph Weber in 1960s. Due to dimensions bars, targeted signal frequencies were kHz range. also pointed out that monitoring vibrations Earth or Moon could reveal mHz band. His Lunar Surface Gravimeter experiment deployed on Apollo 17 crew had a technical...
The advent of stable, highly squeezed states light has generated great interest in the gravitational wave community as a means for improving quantumnoise- limited performance advanced interferometric detectors. To confidently measure these states, it is first necessary to shot-noise across frequency band interest. Technical noise, such non-stationary events, beam pointing, and parasitic interference, can corrupt measurements at low Fourier frequencies, below tens kilo-Hertz. In this paper we...
We propose an upgrade to Advanced LIGO (aLIGO), named LIGO-LF, that focuses on improving the sensitivity in 5--30 Hz low-frequency band, and we explore upgrade's astrophysical applications. present a comprehensive study of detector's technical noises show with technologies currently under development, such as interferometrically sensed seismometers balanced-homodyne readout, LIGO-LF can reach fundamental limits set by quantum thermal down 5 Hz. These are also directly applicable future...
We present the design, control system, and noise analysis of a 6-axis seismometer comprising mass suspended by single fused silica fiber. utilize custom-made, compact Michelson interferometers for readout motion relative to table successfully overcome sensitivity existing commercial seismometers over an order magnitude in angular degrees freedom. develop sensor gravitational-wave observatories, such as LIGO, Virgo, KAGRA, help them observe intermediate-mass black holes, increase their duty...
Squeezed states of light are an important tool for optical measurements below the shot noise limit and realizations quantum information systems. Recently, squeezed vacuum were deployed to enhance limited performance gravitational wave detectors. In most practical implementations squeezing enhancement, relative fluctuations between quadrature angle measured (sometimes called jitter or phase noise) one reduction that can be achieved. We present calculations several effects lead fluctuations,...
A series of recent articles have presented results demonstrating optical cooling macroscopic objects, highlighting the importance this phenomenon for investigations quantum mechanics and its implications thermal noise in gravitational wave detectors. In Letter, we present a measurement off-resonance suspension 1 g oscillator, show that it can be cooled to just 70 mK. The is achieved by using servo impose phase delay between oscillator motion force. model developed how rigidity...
We report on the performance of a dual-wavelength resonant, traveling-wave optical parametric oscillator to generate squeezed light for application in advanced gravitational-wave interferometers. Shot noise suppression 8.6±0.8 dB was measured across detection band interest Advanced LIGO, and controlled squeezing over 5900 s. Our results also demonstrate that design has excellent intracavity backscattered 47 incident 41 dB, which is crucial issue
We present a compact, fibre-coupled interferometer with high sensitivity and large working range.We propose to use this as readout mechanism for future inertial sensors, removing major limiting noise source, in precision positioning systems.The interferometer's peak is 2 × 10 -14 m/ √ Hz at 70 7 -11 mHz.If deployed on GS-13 geophone, the resulting sensing output will be limited by suspension thermal of reference mass from mHz Hz.
The detection of gravitational waves from compact binary mergers by LIGO has opened the era wave astronomy, revealing a previously hidden side cosmos.To maximize reach existing observatory facilities, we have designed new instrument able to detect at distances 5 times further away than possible with Advanced LIGO, or greater 100 event rate.Observations this will make dramatic steps toward understanding physics nearby universe, as well observing universe out cosmological black hole...
Abstract The differential seismic motion between the Internal Seismic Isolation platforms on Advanced Laser Interferometer Gravitational Wave Observatory, affects sensitivity of detector at lower frequencies (below 1 Hz), because each platform moves independently. This induces noise inside cavities auxiliary optics placed platforms, which translates into a higher control effort to maintain stability and resonance. paper shows that can be efficiently measured by Capacitive Position Sensors...
We report on the optical response of a suspended-mass detuned resonant sideband extraction (RSE) interferometer with power recycling. The purpose RSE configuration is to manipulate and optimize differential displacements (induced by gravitational waves) as function frequency, independently other parameters interferometer. design our results in an gain two peaks: resonance at around 4 kHz radiation pressure induced spring 41 Hz. have developed reliable procedure for acquiring lock...
We experimentally demonstrate an inter-satellite laser link acquisition scheme for GRACE Follow-On.In this strategy, dedicated sensors are not required-instead we use the photodetectors and signal processing hardware already required science operation.To establish link, a search over five degrees of freedom must be conducted (± 3 mrad in pitch/yaw each beam, ± 1 GHz frequency difference between two lasers).This is combined with FFT-based peak detection algorithm run on satellite to find...
We present a novel inertial-isolation scheme based on six degree-of-freedom (6D) interferometric sensing of single reference mass. It is capable reducing inertial motion by more than two orders magnitude at 100\,mHz compared with what achievable state-of-the-art seismometers. This will enable substantial improvements in the low-frequency sensitivity gravitational-wave detectors. The inherently two-stage, mass softly suspended within platform to be isolated, which itself from ground. held...
We introduce length-sensing and control schemes for the dual-recycled cavity-enhanced Michelson interferometer configuration proposed Advanced Laser Interferometer Gravitational Wave Observatory (LIGO). discuss principles of this scheme show methods that allow sensing signals to be derived. Experimental verification was carried out in three benchtop experiments are introduced. present implications results from these LIGO other future interferometric gravitational-wave detectors.
In an experiment to simulate the conditions in high optical power advanced gravitational wave detectors, we show for first time that evolution of strong thermal lenses follows predicted infinite sum exponentials (approximated by a double exponential), and such can be compensated using intracavity compensation plate heated on its cylindrical surface. We finesse $\ensuremath{\sim}1400$ achieved cavities with internal plates, mode matching maintained. The achieves front distortion similar...
Abstract We present a modified commercial L-4C geophone with interferometric readout that demonstrates resolution 60 times lower than the included coil-magnet at low frequencies. The intended application for sensor is in vibration isolation platforms require improved performance frequencies 1 Hz. To illustrate it’s controls- and noise-model of an Advanced LIGO ‘HAM-ISI’ system was developed, shows our can reduce residual motion by factor 70 0.1
Atom interferometers employing optical cavities to enhance the beam splitter pulses promise significant advances in science and technology, notably for future gravitational wave detectors. Long cavities, on scale of hundreds meters, have been proposed experiments aiming observe waves with frequencies below 1 Hz, where laser interferometers, such as LIGO, poor sensitivity. Alternatively, short also enhancing sensitivity more portable atom interferometers. We explore fundamental limitations...
The third-generation of gravitational wave observatories, such as the Einstein Telescope (ET) and Cosmic Explorer (CE), aim for an improvement in sensitivity at least a factor ten over wide frequency range compared to current advanced detectors. In order inform design detectors develop qualify their subsystems, dedicated test facilities are required. ETpathfinder prototype uses full interferometer configurations aims provide high facility similar environment ET. Along with interferometry...
We demonstrate the control scheme of an active platform with a six degree freedom (6D) seismometer. The inertial sensor simultaneously measures translational and tilt degrees does not require any additional sensors for stabilization. show that feedforward cancelation can efficiently decouple tilt-to-horizontal coupling seismometer in digital scheme. stabilize frequency band from 250 mHz up to 10 Hz (X, Y) achieve suppression factor 100 around 1 Hz. Further ground vibrations was limited by...
We present results that are a classical analog to quantum noise cancellation. It is possible breach the standard limit in an interferometer by use of squeezing correlate orthogonal quadratures noise, causing their effects on resulting sensitivity cancel. A laser beam incident Fabry-Perot cavity was imprinted with classical, correlated same cause shot and radiation pressure noise. Couplings between these due movable mirror, sensitive pressure, excess This cancellation shown improve signal...
A squeezed light source requires properties such as high squeezing amplitude, bandwidth and stability over time, ideally using few resources, laser power, possible. We compare three nonlinear materials, two of which have not been well characterized for state production, also investigate the viability doubly-resonant optical parametric oscillator cavities in achieving these requirements. model is produced that provides a new way looking at construction an oscillator/optical amplifier setup...
Squeezed states of light have been recently used to improve the sensitivity laser interferometric gravitational-wave detectors beyond quantum limit. To completely establish engineering as a realistic option for next generation detectors, it is crucial study and quantify noise coupling mechanisms which injection squeezed could potentially introduce. We present direct measurement impact backscattered from squeezed-light source deployed on one 4 km long Laser Interferometric Gravitational Wave...
We demonstrate the applicability of EPR entanglement squeezing scheme for enhancing shot-noise-limited sensitivity a detuned dual-recycled Michelson interferometers. In particular, this is applied to GEO\,600 interferometer. The effect losses throughout interferometer, arm length asymmetries, and imperfect separation signal idler beams are considered.