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

arXiv:2506.15885

Slow Light Augmented Fabry-Perot Cavity for Enhanced Sensitivity in Measuring Frequency Shift

Zhu, Ruoxi, Zhou, Zifan, Greenwood, Dustin, Bonacum, Jason, Smith, David D., M. S. Shahriar

Published Jun 18, 2025• 0 citations
arXivHTMLPDF

Abstract

Recently, it has been shown that a slow-light augmented unbalanced Mach-Zehnder interferometer (SLAUMZI) can be used to enhance significantly the sensitivity of measuring the frequency shift of a laser, compared to the heterodyne technique. Here, we show that a similar enhancement can be realized using a slow-light augmented Fabry-Perot Cavity (SLAFPC), due to the fact that an FPC is inherently unbalanced, since different bounces of the field traverse different path lengths before interfering with the other bounces. We show how the degree of enhancement in sensitivity depends on the spectral width of the laser and the finesse of the FPC. For potentially realizable conditions, we show that a sensitivity enhancement factor ~2.8*10^6 can be achieved using a SLAFPC.

DOI
10.48550/arxiv.2506.15885

Related papers

Slow Light Augmented Unbalanced Interferometry for Extreme Enhancement in Sensitivity of Measuring Frequency Shift in a Laser

Ruoxi Zhu, Zifan Zhou, Jinyang Li +3 more

We demonstrate a slow-light augmented unbalanced Mach-Zehnder interferometer (MZI) which can be used to enhance very significantly the sensitivity of measuring the frequency shift in a laser. The factor of enhancement depends on the group index of the slow-light medium, the degree of imbalance between the physical lengths of the two arms of the MZI, and the spectral width of the laser. For a laser with a quantum noise limited spectral width, the group index has to be larger than the finesse of the laser cavity in order to achieve enhancement in measurement sensitivity. For the reported results, slow-light effect is produced by employing electro-magnetically induced transparency via coherent population trapping in a paraffin coated vapor cell of Rb atoms, with a maximum group index of ~2170. The maximum enhancement factor realized is ~70. This differs from the theoretically expected value of ~183 by a factor of ~2.6. This discrepancy can be attributed to effects of unidentified excess noise, and the fact that the test laser spectral width may not the quantum noise limited. Much larger values can potentially be obtained by modifying the apparatus, and using cold atoms for producing the slow-light effect. The sensitivity of any sensor that relies on measuring the frequency shift of a laser can be enhanced substantially using this technique. These include, but are not limited to, gyroscopes and accelerometers based on a conventional ring laser or a superluminal ring laser, and detectors for virialized ultra-light field dark matter.

arXiv:2403.05491•Mar 8, 2024•0 citations

EIT-augmented Unbalanced Mach-Zehnder Interferometer for Enhanced Sensitivity Frequency Measurement

Ruoxi Zhu, Zifan Zhou, Jinyang Li +1 more

We investigated the use of an unbalanced Mach-Zehnder interferometer augmented with slow-light-effect induced via electromagnetically induced transparency for enhanced-sensitivity measurement of frequency shift, and demonstrated conditions corresponding to an enhancement factor greater than ten thousand.

Frontiers in Optics•Jan 1, 2023•0 citations

Controlling the sensitivity of an optical cavity with slow and fast light

David D. Smith, Krishna Myneni, Jamiu A. Odutola +1 more

We measure mode pushing in a Fabry-Perot cavity by a dispersive medium and find that the scale factor increases more than the mode width. We discuss the conditions that result in such enhanced cavity sensitivities.

Advances in Optical Sciences Congress•Jan 1, 2009•1 citation

Brillouin assisted slow-light enhancement via Fabry-Perot cavity effects

César Jáuregui, Periklis Petropoulos, David John Richardson

We show that the presence of a cavity modifies the behaviour of Brillouin-assisted slow light and can be used to significantly enhance the achievable pulse delays. Moreover, the cavity introduces an additional wavelength dependence into the delay versus gain relationship which can be used to provide an extra degree of control within a slow light system. The degree of delay enhancement depends critically both on the cavity finesse and the Brillouin pump power. Our experiments show that delay enhancements greater than 100% can be obtained accompanied by only relatively modest increases in pulse distortion.

Optics Express•Jan 1, 2007•17 citations

Slow light Mach-Zehnder f iber interferometer

Yundong Zhang, Jinfang Wang Jinfang Wang, Xuenan Zhang +4 more

A slow light structure Mach-Zehnder fiber interferometer is theoretically demonstrated.The sensitivity of the interferometer is significantly enhanced by the dispersion of the slow light structure.The numerical results show that the sensitivity enhancement factor varies with the coupling coefficient and reaches its maximum under critical coupling conditions.

Chinese Optics Letters•Jan 1, 2012•2 citations

Slow light Mach-Zehnder fiber interferometer

掌蕴东, 王金芳, 张学楠 +4 more

A slow light structure Mach-Zehnder fiber interferometer is theoretically demonstrated. The sensitivity of the interferometer is significantly enhanced by the dispersion of the slow light structure. The numerical results show that the sensitivity enhancement factor varies with the coupling coefficient and reaches its maximum under critical coupling conditions.

Chinese Optics Letters•Jan 1, 2012•0 citations
Recently, it has been shown that a slow-light augmented unbalanced Mach-Zehnder interferometer (SLAUMZI) can be used to enhance significantly the sensitivity of measuring the frequency shift of a laser, compared to the heterodyne technique. Here, we show that a similar enhancement can be realized using a slow-light augmented Fabry-Perot Cavity (SLAFPC), due to the fact that an FPC is inherently unbalanced, since different bounces of the field traverse different path lengths before interfering with the other bounces. We show how the degree of enhancement in sensitivity depends on the spectral width of the laser and the finesse of the FPC. For potentially realizable conditions, we show that a sensitivity enhancement factor ~2.8*10^6 can be achieved using a SLAFPC.
We demonstrate a slow-light augmented unbalanced Mach-Zehnder interferometer (MZI) which can be used to enhance very significantly the sensitivity of measuring the frequency shift in a laser. The factor of enhancement depends on the group index of the slow-light medium, the degree of imbalance between the physical lengths of the two arms of the MZI, and the spectral width of the laser. For a laser with a quantum noise limited spectral width, the group index has to be larger than the finesse of the laser cavity in order to achieve enhancement in measurement sensitivity. For the reported results, slow-light effect is produced by employing electro-magnetically induced transparency via coherent population trapping in a paraffin coated vapor cell of Rb atoms, with a maximum group index of ~2170. The maximum enhancement factor realized is ~70. This differs from the theoretically expected value of ~183 by a factor of ~2.6. This discrepancy can be attributed to effects of unidentified excess noise, and the fact that the test laser spectral width may not the quantum noise limited. Much larger values can potentially be obtained by modifying the apparatus, and using cold atoms for producing the slow-light effect. The sensitivity of any sensor that relies on measuring the frequency shift of a laser can be enhanced substantially using this technique. These include, but are not limited to, gyroscopes and accelerometers based on a conventional ring laser or a superluminal ring laser, and detectors for virialized ultra-light field dark matter.
We show that the presence of a cavity modifies the behaviour of Brillouin-assisted slow light and can be used to significantly enhance the achievable pulse delays. Moreover, the cavity introduces an additional wavelength dependence into the delay versus gain relationship which can be used to provide an extra degree of control within a slow light system. The degree of delay enhancement depends critically both on the cavity finesse and the Brillouin pump power. Our experiments show that delay enhancements greater than 100% can be obtained accompanied by only relatively modest increases in pulse distortion.