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 and Quantum Sensing and Precision Metrology II

A high-finesse suspended interferometric sensor for macroscopic quantum mechanics with femtometer sensitivity

Tianliang Yan, J. Smetana, Artemiy V. Dmitriev, Vincent Boyer, Д. В. Мартынов

Published Mar 19, 2025• 0 citations
Publisher

Abstract

We present our development of a table-top quantum sensor with femtometer sensitivity within the acoustic frequency band. Our sensor utilises the expertise developed within the gravitational-wave community, particularly in the control of high-finesse, suspended interferometers, and the mitigation of seismic and thermal noise. We construct a system consisting of a cryostat-mounted four-stage suspension supporting two cavities with optical finesse in excess of 350,000. We use active isolation of the entire cryostat system to achieve an order-of-magnitude of reduction of the seismic noise prior to the passive isolation of the internal suspension. We achieve the femtometer sensitivity using a custom-made phase lock loop. With further enhancements to the readout electronics and suspension characteristics, we aim to reach the quantum radiation pressure noise. This sensor holds the potential for future applications in demonstrating macroscopic entanglement and testing semi-classical and quantum gravity theories.

DOI
10.1117/12.3043664

Related papers

Towards the Standard Quantum Limit in a Table-Top Interferometer

Д. В. Мартынов, J. Smetana

We discuss the development and expected performance of a table-top experiment for measuring quantum fluctuations in a suspended-test-mass interferometer. The ultimate goal of this experiment is to perform measurements of the quantum noise-limited displacement sensitivity of the interferometer at the level of the standard quantum limit (5×10−19 m/sqrt(Hz) at 100 Hz). The case is made for an experiment that will show the feasibility of preparing a macroscopic quantum-limited system within a regular laboratory environment. This will be achieved by suspending a cryogenically cooled, high-finesse, optical cavity via a multi-stage suspension. We motivate the utility of our experiment in providing an increased understanding of the nature of quantum fluctuations in current and future gravitational wave detectors, as well as opening an avenue for research into aspects of macroscopic quantum mechanics and quantum gravity. We explain how these requirements drove our design specification. Given the extremely small displacements in question, particular attention is devoted to discussing noise mitigation, with a focus on the suppression of seismic and thermal noise.

•Apr 23, 2020•1 citation

Small scale Suspended Interferometer for Ponderomotive Squeezing (SIPS) as test bench of the EPR squeezer for Advanced Virgo

S. Di Pace, Luca Naticchioni, ETTORE MAJORANA +13 more

We are developing a small-scale interferometer with monolithic suspension of test masses (SIPS), that will be sensitive to the quantum radiation pressure noise in the audio frequency band of gravitational wave detectors. In the same time, a table-top experiment for the frequency dependent squeezing generation, through the Einstein Podolsky Rosen (EPR) principle, is under construction. SIPS interferometer, being designed to achieve the quantum radiation pressure noise limit exploiting high finesse optical cavities, turns out to be a suitable test bench for the EPR technique, before a possible integration in Virgo for broadband quantum noise reduction. In this work, we describe the concept of the SIPS experiment, the most important noises affecting this setup, and we briefly present the current status and the plan for the integration with the EPR squeezing experiment.

•Apr 23, 2020•3 citations

Broadband Quantum Noise Reduction In A Small-Scale Suspended Interferometer With Quantum Entangled Squeezed Beams

W. Ali, B. Garaventa, S. Di Pace +3 more

General relativity predicts the existence of gravitational waves (GWs), ripples in spacetime that are now observable to highly sensitive interferometers. However, quantum noise poses a significant challenge for gravitational wave (GW) interferometers, influencing the entire bandwidth range (10-10,000 Hz) of the current GW detectors. At higher frequencies, shot noise (SN) predominates, while at lower frequencies, radiation-pressure noise (RPN) becomes the limiting factor, reducing both sensitivity and measurement precision. Squeezing techniques are implemented to address this issue by confining uncertainty within one quadrature of the light field. Starting from the observing run, O4 Virgo and LIGO have enhanced this method through frequency-dependent squeezing (FDS). By employing a 300-meter-long detuned filter cavity, the squeezing ellipse is rotated, allowing phase squeezing at high frequencies to reduce and amplitude squeezing at low frequencies to mitigate RPN, ultimately refining detection capabilities across the frequency spectrum. A promising alternative technique to reduce quantum noise across the entire sensitivity band uses Einstein-Podolsky-Rosen (EPR) quantum entanglement. This approach involves injecting two entangled squeezed beams at different frequencies into the dark port of the interferometer, enabling it to act as both a filter cavity and a gravitational wave detector. The Suspended Interferometer for Ponderomotive Squeezing (SIPS) adopts a large-scale GW detector layout, with a Michelson configuration and Fabry-Perot arm cavities. This system was initially thought to generate FDS in the GW frequency band using the ponderomotive technique. To enhance stability, a precise local control system was developed for the main optics of SIPS, which are suspended in a double pendulum configuration with monolithic fibers to reduce thermal noise. Advanced PXI-based data acquisition and position-sensitive detectors (PSDs) monitor angular and linear displacements, while real-time signal processing in LabVIEW enables corrective actuation, marking a significant step toward improved alignment and noise reduction in GW interferometry. The paper highlights the current status of SIPS, focusing on the local control strategy, underscoring its potential impact on the field.

International Journal of Environmental Sciences•Aug 4, 2025•0 citations

Reaching a macroscopic quantum state in a suspended interferometer

J. Smetana, Tianliang Yan, Vincent Boyer +1 more

Interferometric sensors provide an excellent opportunity for studying novel aspects of quantum mechanics. In this paper, we present the updated design for a suspended, cryogenically cooled table-top interferometer that can operate at the standard quantum limit of sensitivity. In this mode of operation, we will be able to probe aspects of macroscopic entanglement, quantum correlations, and semi-classical and quantum gravity models. We present the up-to-date experimental progress as well as the results of ongoing investigations.

Quantum Technology: Driving Commercialisation of an Enabling Science•Jan 11, 2023•1 citation

Beating quantum limits in interferometers with quantum locking of mirrors

A. Heidmann, Jean-Michel Courty, M. Pinard +7 more

The sensitivity in interferometric measurements such as gravitational-wave detectors is ultimately limited by quantum noise of light. We discuss the use of feedback mechanisms to reduce the quantum effects of radiation pressure. Recent experiments have shown that it is possible to reduce the thermal motion of a mirror by cold damping. The mirror motion is measured with anoptomechanical sensor based on a high-finesse cavity, and reduced by a feedback loop. We show that this technique can be extended to lock the mirror at the quantum level. In gravitational-waves interferometers with Fabry-Perot cavities in each arms, it is even possible to use a single feedback mechanism to lock one cavity mirror on the other. This quantum locking greatly improves the sensitivity of the interferometric measurement. It is furthermore insensitive to imperfections such as losses in the interferometer.

•Jan 1, 2004•7 citations

Beating quantum limits in interferometers with quantum locking of mirrors

A. Heidmann, Jean-Michel Courty, M. Pinard +1 more

The sensitivity in interferometric measurements such as gravitational-wave detectors is ultimately limited by quantum noise of light. We discuss the use of feedback mechanisms to reduce the quantum effects of radiation pressure. Recent experiments have shown that it is possible to reduce the thermal motion of a mirror by cold damping. The mirror motion is measured with an optomechanical sensor based on a high-finesse cavity, and reduced by a feedback loop. We show that this technique can be extended to lock the mirror at the quantum level. In gravitational-waves interferometers with Fabry-Perot cavities in each arms, it is even possible to use a single feedback mechanism to lock one cavity mirror on the other. This quantum locking greatly improves the sensitivity of the interferometric measurement. It is furthermore insensitive to imperfections such as losses in the interferometer.

arXiv:quant-ph/0311167•Journal of Optics B Quantum and Semiclassical Optics•Jul 28, 2004•10 citations
We present our development of a table-top quantum sensor with femtometer sensitivity within the acoustic frequency band. Our sensor utilises the expertise developed within the gravitational-wave community, particularly in the control of high-finesse, suspended interferometers, and the mitigation of seismic and thermal noise. We construct a system consisting of a cryostat-mounted four-stage suspension supporting two cavities with optical finesse in excess of 350,000. We use active isolation of the entire cryostat system to achieve an order-of-magnitude of reduction of the seismic noise prior to the passive isolation of the internal suspension. We achieve the femtometer sensitivity using a custom-made phase lock loop. With further enhancements to the readout electronics and suspension characteristics, we aim to reach the quantum radiation pressure noise. This sensor holds the potential for future applications in demonstrating macroscopic entanglement and testing semi-classical and quantum gravity theories.
We discuss the development and expected performance of a table-top experiment for measuring quantum fluctuations in a suspended-test-mass interferometer. The ultimate goal of this experiment is to perform measurements of the quantum noise-limited displacement sensitivity of the interferometer at the level of the standard quantum limit (5×10−19 m/sqrt(Hz) at 100 Hz). The case is made for an experiment that will show the feasibility of preparing a macroscopic quantum-limited system within a regular laboratory environment. This will be achieved by suspending a cryogenically cooled, high-finesse, optical cavity via a multi-stage suspension. We motivate the utility of our experiment in providing an increased understanding of the nature of quantum fluctuations in current and future gravitational wave detectors, as well as opening an avenue for research into aspects of macroscopic quantum mechanics and quantum gravity. We explain how these requirements drove our design specification. Given the extremely small displacements in question, particular attention is devoted to discussing noise mitigation, with a focus on the suppression of seismic and thermal noise.
We are developing a small-scale interferometer with monolithic suspension of test masses (SIPS), that will be sensitive to the quantum radiation pressure noise in the audio frequency band of gravitational wave detectors. In the same time, a table-top experiment for the frequency dependent squeezing generation, through the Einstein Podolsky Rosen (EPR) principle, is under construction. SIPS interferometer, being designed to achieve the quantum radiation pressure noise limit exploiting high finesse optical cavities, turns out to be a suitable test bench for the EPR technique, before a possible integration in Virgo for broadband quantum noise reduction. In this work, we describe the concept of the SIPS experiment, the most important noises affecting this setup, and we briefly present the current status and the plan for the integration with the EPR squeezing experiment.
General relativity predicts the existence of gravitational waves (GWs), ripples in spacetime that are now observable to highly sensitive interferometers. However, quantum noise poses a significant challenge for gravitational wave (GW) interferometers, influencing the entire bandwidth range (10-10,000 Hz) of the current GW detectors. At higher frequencies, shot noise (SN) predominates, while at lower frequencies, radiation-pressure noise (RPN) becomes the limiting factor, reducing both sensitivity and measurement precision. Squeezing techniques are implemented to address this issue by confining uncertainty within one quadrature of the light field. Starting from the observing run, O4 Virgo and LIGO have enhanced this method through frequency-dependent squeezing (FDS). By employing a 300-meter-long detuned filter cavity, the squeezing ellipse is rotated, allowing phase squeezing at high frequencies to reduce and amplitude squeezing at low frequencies to mitigate RPN, ultimately refining detection capabilities across the frequency spectrum. A promising alternative technique to reduce quantum noise across the entire sensitivity band uses Einstein-Podolsky-Rosen (EPR) quantum entanglement. This approach involves injecting two entangled squeezed beams at different frequencies into the dark port of the interferometer, enabling it to act as both a filter cavity and a gravitational wave detector. The Suspended Interferometer for Ponderomotive Squeezing (SIPS) adopts a large-scale GW detector layout, with a Michelson configuration and Fabry-Perot arm cavities. This system was initially thought to generate FDS in the GW frequency band using the ponderomotive technique. To enhance stability, a precise local control system was developed for the main optics of SIPS, which are suspended in a double pendulum configuration with monolithic fibers to reduce thermal noise. Advanced PXI-based data acquisition and position-sensitive detectors (PSDs) monitor angular and linear displacements, while real-time signal processing in LabVIEW enables corrective actuation, marking a significant step toward improved alignment and noise reduction in GW interferometry. The paper highlights the current status of SIPS, focusing on the local control strategy, underscoring its potential impact on the field.
Interferometric sensors provide an excellent opportunity for studying novel aspects of quantum mechanics. In this paper, we present the updated design for a suspended, cryogenically cooled table-top interferometer that can operate at the standard quantum limit of sensitivity. In this mode of operation, we will be able to probe aspects of macroscopic entanglement, quantum correlations, and semi-classical and quantum gravity models. We present the up-to-date experimental progress as well as the results of ongoing investigations.
The sensitivity in interferometric measurements such as gravitational-wave detectors is ultimately limited by quantum noise of light. We discuss the use of feedback mechanisms to reduce the quantum effects of radiation pressure. Recent experiments have shown that it is possible to reduce the thermal motion of a mirror by cold damping. The mirror motion is measured with anoptomechanical sensor based on a high-finesse cavity, and reduced by a feedback loop. We show that this technique can be extended to lock the mirror at the quantum level. In gravitational-waves interferometers with Fabry-Perot cavities in each arms, it is even possible to use a single feedback mechanism to lock one cavity mirror on the other. This quantum locking greatly improves the sensitivity of the interferometric measurement. It is furthermore insensitive to imperfections such as losses in the interferometer.
The sensitivity in interferometric measurements such as gravitational-wave detectors is ultimately limited by quantum noise of light. We discuss the use of feedback mechanisms to reduce the quantum effects of radiation pressure. Recent experiments have shown that it is possible to reduce the thermal motion of a mirror by cold damping. The mirror motion is measured with an optomechanical sensor based on a high-finesse cavity, and reduced by a feedback loop. We show that this technique can be extended to lock the mirror at the quantum level. In gravitational-waves interferometers with Fabry-Perot cavities in each arms, it is even possible to use a single feedback mechanism to lock one cavity mirror on the other. This quantum locking greatly improves the sensitivity of the interferometric measurement. It is furthermore insensitive to imperfections such as losses in the interferometer.