Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Log inSign up
Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Blog
Job Board
Q3AS

© 2026 Aqora Quantum S.A.S.

TermsPrivacyLegal Notice

Optical Fiber Communication Conference

Precision Interferometry for Gravitational Waves: How Squeezed States Can Improve Astrophysical Observation Range

E. Polini

Published Jan 1, 2026• 0 citations
Publisher

Abstract

Quantum noise fundamentally limits the sensitivity of gravitational-wave detectors. It has been demonstrated that injecting frequency-dependent squeezed vacuum states reduces quantum noise across the full detection band, extending the observable universe volume and paving the way for next-generation interferometers.
DOI
10.1364/ofc.2026.th1f.4

Related papers

Squeezed vacuum states of light for gravitational wave detectors

L. Barsotti, J. Harms, Roman Schnabel

A century after Einstein's formulation of general relativity, the detectors of the Laser Interferometer Gravitational-wave Observatory (LIGO) made the first direct detection of gravitational waves. This historic achievement was the culmination of a world-wide effort and decades of instrument research. While sufficient for this monumental discovery, the current generation of gravitational-wave detectors represent the least sensitive devices necessary for the task; improved detectors will be required to fully exploit this new window on the Universe. In this paper, we review the application of squeezed vacuum states of light to gravitational-wave detectors as a way to reduce quantum noise, which currently limits their performance in much of the detection band.

Reports on Progress in Physics•Mar 23, 2018•139 citations

Quantum noise enhancement for gravitational wave detectors: Status of squeezed vacuum research at TAMA and KAGRA

M. A. Page, M. Eisenmann, Yang Zhao +27 more

The current generation of gravitational wave laser interferometer detectors operate at the sensitivity limit imposed by quantum uncertainty of photon amplitude and phase quadratures. Heisenberg's principle dictates that the product of amplitude and phase uncertainty must be above a certain value, but apart from that we can still manipulate either quadrature to achieve quantum noise reduction, since the effect of amplitude and phase uncertainty is frequency dependent in gravitational wave detectors. This is the crux of the frequency dependent squeezing technique, which reduces quantum amplitude uncertainty at low frequency and quantum phase uncertainty at high frequency, where these respective quadratures each dominate. Thus, we can reduce quantum noise across the entire detection band. However, this technique is extremely sensitive to optical losses at all parts of the squeezing generation chain, and so far only a low degree of broadband squeezing has been observed. This proceeding outlines the current status of squeezing research at the former TAMA300 gravitational wave detector at the National Astronomical Observatory of Japan, where we aim to improve the level of achievable broadband squeezing. An update is also given regarding design and noise of squeezed injection for the underground gravitational wave detector KAGRA located in Gifu, Japan.

International Cosmic Ray Conference•Jul 27, 2023•1 citation

Squeezed Light for Future Gravitational Wave Detectors

Fabian Meylahn, B. Willke, H. Vahlbruch

Squeezed vacuum states of light show a reduction in quantum noise along one quadrature compared to the vacuum state. This characteristic is the key to improve interferometric measurements beyond their quantum noise limitation. In particular for ground-based gravitational wave detectors [1] the application of squeezed light led to a significant sensitivity improvement of up to 6 dB. Future gravitational wave detectors, like the Einstein Telescope [2] or Cosmic Explorer [3], aim for an even higher enhancement in the range of 10 dB with the injection of squeezed states of light into the dark port of their interferometers.

Conference on Lasers and Electro-Optics Europe & European Quantum Electronics Conference (CLEO/Europe-EQEC)•Jun 26, 2023•0 citations

Quantum noise reduction in Advanced Virgo

V. Sequino

Abstract In order to detect the small distance variations induced by gravitational waves, very sensitive devices must be used. Gravitational wave detectors are sophisticated interferometers sensitive even to vacuum fluctuations. These latter are responsible for quantum noise. Due to the frequency-dependent response of gravitational wave interferometers, quantum noise manifests itself as radiation pressure noise for frequencies below 100 Hz, while as shot noise for higher frequencies. The solution that has been adopted in order to reduce quantum noise is the injection, through the interferometer output port, of vacuum states, called squeezed, whose amplitude and phase uncertainties are correlated. A frequency-independent squeezing technique, as a method for the reduction of the quantum noise, has been already demonstrated in long-arm interferometers. Radiation pressure noise does not limit the sensitivity of the present interferometers, being this completely covered by other noises. But, in the near future, these noises will be reduced and also this quantum noise component will be relevant. The adopted solution to have a broad-band quantum noise reduction is a frequency-dependent squeezing technique. In this paper the results obtained in Advanced Virgo using the frequency-independent squeezing technique will be shown. Moreover the conceptual design for the implementation of the frequency-dependent squeezing will be presented.

Physica Scripta•Jun 21, 2021•5 citations

Quantum noise reduction for gravitational-wave interferometers with non-classical states

M. J. Yap

The detection of the binary neutron star inspiral GW170817 by the Advanced Laser Interferometer Gravitational Wave Observatory (LIGO) and Advanced Virgo, followed by counterpart observations across a broad electromagnetic spectrum, marks the dawn of multi-messenger astronomy. The discovery rate and potential of gravitational-wave astronomy is limited by the detector's sensitivity. A key challenge in improving the sensitivity of gravitational-wave detectors is to reduce quantum noise which arises due to the quantum nature of light. A well established technique to reduce the quantum noise in the detector is by replacing the coherent vacuum fluctuations entering the readout port with a squeezed vacuum state. This technique has been successfully demonstrated at the GEO-600 and LIGO Hanford detector, and is now in routine operation in current gravitational wave detectors. This thesis presents research from three experiments to develop quantum noise reduction techniques for next-generation gravitational wave detector using non-classical quantum states such as squeezed states. Current proposals for future generation gravitational wave detectors, such as LIGO Voyager, plan to utilise cryogenic silicon instead of fused silica as the test mass material. This is to improve the power handling of the detector and reduce thermal noise. The switch to silicon test masses requires a change of laser wavelength to the 2 micron region. In the first experiment, we built and operated the first squeezed vacuum source at a wavelength of 1984 nm. With a stable squeezing ellipse phase control employed, 3.9 dB of squeezing was measured, predominately limited by losses due to the low quantum efficiency of the photodiode. The squeezed vacuum system presented is compatible with future detectors and is a key pathfinder experiment to inform the design of cryogenic silicon interferometers. The quantum nature of light results in quantum radiation pressure noise that limits the low frequency sensitivity of gravitational wave detectors. In collaboration with Louisiana State University, the second experiment demonstrates the reduction of quantum radiation pressure noise by injecting bright squeezed light into a centimetre-scale optomechanical cavity at room temperature. The experiment involves the development and integration of a low-frequency bright squeezed source to reduce the quantum radiation pressure noise by 1.2 dB at 20 kHz. The result also represents the lowest frequency bright squeezed state measured from a crystal-based squeezer. Quadrature rotation of the injected squeezed state is required to achieve broadband quantum noise reduction in gravitational wave detectors due to the quantum back-action effect. This requires the squeezed state to interact with a low loss optical filter with a low frequency bandwidth prior to injection and represents a significant technical challenge. The final experiment presented in this thesis demonstrates an alternate method where frequency-dependent squeezing with Einstein-Podolsky-Rosen (EPR) entangled states is generated. When integrated into a gravitational wave detector, the alternate method allows the detector to simultaneously serve as the optical filter, eliminating the need for the additional apparatus.

•Jan 1, 2020•0 citations

Quantum Entanglement and its Role in Enhancing the Sensitivity of Gravitational Wave Detectors: A Theoretical Exploration

Akash Verma

This paper explores the theoretical potential of utilizing quantum entanglement, specifically through the generation and application of squeezed states of light, to enhance the sensitivity of gravitational wave detectors. We delve into the fundamental limitations imposed by quantum noise in conventional interferometric detectors and investigate how the injection of squeezed states can circumvent these limitations. We present a detailed theoretical framework for implementing squeezed light in advanced gravitational wave observatories and analyze the expected improvements in signal-to-noise ratio. The analysis includes a rigorous treatment of the quantum mechanical interactions within the interferometer, considering realistic experimental imperfections. Our findings suggest that the strategic deployment of quantum entanglement offers a promising pathway towards significantly improving the detection capabilities of future gravitational wave detectors, opening new avenues for exploring the universe.

JANOLI International Journal of Physics•Jan 8, 2025•0 citations
A century after Einstein's formulation of general relativity, the detectors of the Laser Interferometer Gravitational-wave Observatory (LIGO) made the first direct detection of gravitational waves. This historic achievement was the culmination of a world-wide effort and decades of instrument research. While sufficient for this monumental discovery, the current generation of gravitational-wave detectors represent the least sensitive devices necessary for the task; improved detectors will be required to fully exploit this new window on the Universe. In this paper, we review the application of squeezed vacuum states of light to gravitational-wave detectors as a way to reduce quantum noise, which currently limits their performance in much of the detection band.
The current generation of gravitational wave laser interferometer detectors operate at the sensitivity limit imposed by quantum uncertainty of photon amplitude and phase quadratures. Heisenberg's principle dictates that the product of amplitude and phase uncertainty must be above a certain value, but apart from that we can still manipulate either quadrature to achieve quantum noise reduction, since the effect of amplitude and phase uncertainty is frequency dependent in gravitational wave detectors. This is the crux of the frequency dependent squeezing technique, which reduces quantum amplitude uncertainty at low frequency and quantum phase uncertainty at high frequency, where these respective quadratures each dominate. Thus, we can reduce quantum noise across the entire detection band. However, this technique is extremely sensitive to optical losses at all parts of the squeezing generation chain, and so far only a low degree of broadband squeezing has been observed. This proceeding outlines the current status of squeezing research at the former TAMA300 gravitational wave detector at the National Astronomical Observatory of Japan, where we aim to improve the level of achievable broadband squeezing. An update is also given regarding design and noise of squeezed injection for the underground gravitational wave detector KAGRA located in Gifu, Japan.
Squeezed vacuum states of light show a reduction in quantum noise along one quadrature compared to the vacuum state. This characteristic is the key to improve interferometric measurements beyond their quantum noise limitation. In particular for ground-based gravitational wave detectors [1] the application of squeezed light led to a significant sensitivity improvement of up to 6 dB. Future gravitational wave detectors, like the Einstein Telescope [2] or Cosmic Explorer [3], aim for an even higher enhancement in the range of 10 dB with the injection of squeezed states of light into the dark port of their interferometers.
Abstract In order to detect the small distance variations induced by gravitational waves, very sensitive devices must be used. Gravitational wave detectors are sophisticated interferometers sensitive even to vacuum fluctuations. These latter are responsible for quantum noise. Due to the frequency-dependent response of gravitational wave interferometers, quantum noise manifests itself as radiation pressure noise for frequencies below 100 Hz, while as shot noise for higher frequencies. The solution that has been adopted in order to reduce quantum noise is the injection, through the interferometer output port, of vacuum states, called squeezed, whose amplitude and phase uncertainties are correlated. A frequency-independent squeezing technique, as a method for the reduction of the quantum noise, has been already demonstrated in long-arm interferometers. Radiation pressure noise does not limit the sensitivity of the present interferometers, being this completely covered by other noises. But, in the near future, these noises will be reduced and also this quantum noise component will be relevant. The adopted solution to have a broad-band quantum noise reduction is a frequency-dependent squeezing technique. In this paper the results obtained in Advanced Virgo using the frequency-independent squeezing technique will be shown. Moreover the conceptual design for the implementation of the frequency-dependent squeezing will be presented.
The detection of the binary neutron star inspiral GW170817 by the Advanced Laser Interferometer Gravitational Wave Observatory (LIGO) and Advanced Virgo, followed by counterpart observations across a broad electromagnetic spectrum, marks the dawn of multi-messenger astronomy. The discovery rate and potential of gravitational-wave astronomy is limited by the detector's sensitivity. A key challenge in improving the sensitivity of gravitational-wave detectors is to reduce quantum noise which arises due to the quantum nature of light. A well established technique to reduce the quantum noise in the detector is by replacing the coherent vacuum fluctuations entering the readout port with a squeezed vacuum state. This technique has been successfully demonstrated at the GEO-600 and LIGO Hanford detector, and is now in routine operation in current gravitational wave detectors. This thesis presents research from three experiments to develop quantum noise reduction techniques for next-generation gravitational wave detector using non-classical quantum states such as squeezed states. Current proposals for future generation gravitational wave detectors, such as LIGO Voyager, plan to utilise cryogenic silicon instead of fused silica as the test mass material. This is to improve the power handling of the detector and reduce thermal noise. The switch to silicon test masses requires a change of laser wavelength to the 2 micron region. In the first experiment, we built and operated the first squeezed vacuum source at a wavelength of 1984 nm. With a stable squeezing ellipse phase control employed, 3.9 dB of squeezing was measured, predominately limited by losses due to the low quantum efficiency of the photodiode. The squeezed vacuum system presented is compatible with future detectors and is a key pathfinder experiment to inform the design of cryogenic silicon interferometers. The quantum nature of light results in quantum radiation pressure noise that limits the low frequency sensitivity of gravitational wave detectors. In collaboration with Louisiana State University, the second experiment demonstrates the reduction of quantum radiation pressure noise by injecting bright squeezed light into a centimetre-scale optomechanical cavity at room temperature. The experiment involves the development and integration of a low-frequency bright squeezed source to reduce the quantum radiation pressure noise by 1.2 dB at 20 kHz. The result also represents the lowest frequency bright squeezed state measured from a crystal-based squeezer. Quadrature rotation of the injected squeezed state is required to achieve broadband quantum noise reduction in gravitational wave detectors due to the quantum back-action effect. This requires the squeezed state to interact with a low loss optical filter with a low frequency bandwidth prior to injection and represents a significant technical challenge. The final experiment presented in this thesis demonstrates an alternate method where frequency-dependent squeezing with Einstein-Podolsky-Rosen (EPR) entangled states is generated. When integrated into a gravitational wave detector, the alternate method allows the detector to simultaneously serve as the optical filter, eliminating the need for the additional apparatus.
This paper explores the theoretical potential of utilizing quantum entanglement, specifically through the generation and application of squeezed states of light, to enhance the sensitivity of gravitational wave detectors. We delve into the fundamental limitations imposed by quantum noise in conventional interferometric detectors and investigate how the injection of squeezed states can circumvent these limitations. We present a detailed theoretical framework for implementing squeezed light in advanced gravitational wave observatories and analyze the expected improvements in signal-to-noise ratio. The analysis includes a rigorous treatment of the quantum mechanical interactions within the interferometer, considering realistic experimental imperfections. Our findings suggest that the strategic deployment of quantum entanglement offers a promising pathway towards significantly improving the detection capabilities of future gravitational wave detectors, opening new avenues for exploring the universe.