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

Experimental Ultra-small Longitudinal Phase Estimation via Weak Measurement Amplification

Mengjun Hu, Xiao‐Min Hu, Bi‐Heng Liu, Yun‐Feng Huang, Chuan‐Feng Li, Guang‐Can Guo, Yong-Sheng Zhang

Published Jan 1, 2018• 2 citations
Publisher

Abstract

Weak value amplification has been applied to various small physical quantities estimation, however there still lacks a practical feasible protocol to amplify ultra-small longitudinal phase, which is of importance in high precision measurement. Very recently, a different amplification protocol within the framework of weak measurements is proposed to solve this problem, which is capable of measuring any ultra-small longitudinal phase signal that conventional interferometry tries to do. Here we experimentally demonstrate this weak measurements amplification protocol of ultra-small longitudinal phase and realize one order of magnitude amplification in the same technical condition, which verifies the validity of the protocol and show higher precision and sensitivity than conventional interferometry. Our results significantly broaden the area of applications of weak measurements and may play an important role in high precision measurements.

DOI
10.13140/rg.2.2.35151.38569

Related papers

Measuring Small Longitudinal Phase Shifts via Weak Measurement Amplification

Kai Xu, Xiao‐Min Hu, Chao ZHang +6 more

Weak measurement amplification, which is considered as a very promising scheme in precision measurement, has been applied to various small physical quantities estimation. Since many quantities can be converted to phase signal, it is thus interesting and important to consider measuring ultra-small longitudinal phase shifts by using weak measurement. Here, we propose and experimentally demonstrate a novel weak measurement amplification based ultra-small longitudinal phase estimation, which is suitable for polarization interferometry. We realize one order of magnitude amplification measurement of small phase signal directly introduced by Liquid Crystal Variable Retarder and show its robust to finite visibility of interference. Our results may find important applications in high-precision measurements, such as gravitational waves detection.

arXiv:1803.07746•Mar 21, 2018•0 citations

Measuring small longitudinal phase shifts via weak measurement amplification

Kai Xu, Xiao-Min 晓敏 Hu 胡, Meng-Jun 孟军 Hu 胡 +7 more

Weak measurement amplification, which is considered as a very promising scheme in precision measurement, has been applied to various small physical quantities estimations. Since many physical quantities can be converted into phase signals, it is interesting and important to consider measuring small longitudinal phase shifts by using weak measurement. Here, we propose and experimentally demonstrate a novel weak measurement amplification-based small longitudinal phase estimation, which is suitable for polarization interferometry. We realize one order of magnitude amplification measurement of a small phase signal directly introduced by a liquid crystal variable retarder and show that it is robust to the imperfection of interference. Besides, we analyze the effect of magnification error which is never considered in the previous works, and find the constraint on the magnification. Our results may find important applications in high-precision measurements, e.g., gravitational wave detection.

Chinese Physics B•Jan 9, 2024•4 citations

Toward ultrahigh sensitivity in weak-value amplification

Jingzheng Huang, Yanjia Li, Chen Fang +2 more

Achieving higher sensitivity is an earnest purpose for precision metrology. As a response to this goal, the weak-value amplification approach has been developed for measuring ultrasmall physical effects, realizing sensitivity that had never been reached before. Encouraged by the successes, many efforts have been devoted to obtain ultimate sensitivity of weak-value amplification. However, the benefit would be easily compromised in practice, because the cost of significant reduction on signal intensity leads to an ultralow signal-to-noise ratio. In this work, we bridge this gap by proposing an alternative weak-value amplification approach, which provides sensitivity several orders of magnitude higher than the standard approach while being compatible with practical imperfections. In the proof-of-principle experiment of measuring longitudinal phase change in time domain, sensitivity up to $5\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}4}$ attosecond is exemplified. Our approach can be applied to measure other small parameters with extremely high sensitivity, providing a method for future precision metrology.

arXiv:1907.02168•Physical Review A•Jul 11, 2019•38 citations

Realization of ultra-small stress birefringence detection with weak-value amplification technique

Yongsheng Wang, Shizhen Chen, Shuangchun Wen +1 more

How to realize the detection of tiny birefringence is an important but challenging issue for investigations and applications in optics. In weak measurements, weak-value amplification has been widely applied to the precise estimation of time delay. Here, we show that the linear amplification in weak measurements has the potential to outperform standard weak-value amplification for ultra-small parameter characterization. The higher measurement accuracy in the linear amplification enables us to achieve a measurement of stress-induced birefringence with a high resolution of 5×10−10. Compared with existing methods, the accuracy based on weak measurements for birefringence detection can improve two orders of magnitude. Our method may have important applications in a variety of fields involving the precise measurement of time delay or birefringence.

Applied Physics Letters•Apr 19, 2021•20 citations

Sub-nanometer optical path difference measurement using biased weak measurement with real weak values

Huang Jing-Hui, Jingzheng Huang, Hongliang Cui +5 more

We experimentally demonstrate an ultra-sensitive technique for measuring sub-nanometer optical path differences (OPDs) using the biased weak measurement (BWM) protocol. By employing real weak values with a classical coherent light source and introducing a bias phase procedure, this method directly amplifies small OPDs in interferometry, achieving significantly enhanced amplification compared to conventional measurement (CM) and standard weak measurement (SWM). In a proof-of-principle experiment of sub-nanometer OPD measurement, BWM achieves nearly 4× signal improvement within the linear response range relative to SWM, and an 85× improvement over CM. The signal-to-noise ratio of BWM and SWM exhibits an order-of-magnitude enhancement on average compared to CM. Furthermore, we experimentally determine a minimum OPD resolution of 3.1×10-4nm, corresponding to a time delay of 1 ×10-3attoseconds and a phase shift of 3.0× 10-6rad. These results highlight the potential of weak measurement protocols for high-precision longitudinal phase estimation using narrow-band sources and common optical components.

•Mar 26, 2026•0 citations

Sub-nanometer optical path difference measurement using biased weak measurement with real weak values

Huang Jing-Hui, Jingzheng Huang, Hongliang Cui +5 more

We experimentally demonstrate an ultra-sensitive technique for measuring sub-nanometer optical path differences (OPDs) using the biased weak measurement (BWM) protocol. By employing real weak values with a classical coherent light source and introducing a bias phase procedure, this method directly amplifies small OPDs in interferometry, achieving significantly enhanced amplification compared to conventional measurement (CM) and standard weak measurement (SWM). In a proof-of-principle experiment of sub-nanometer OPD measurement, BWM achieves nearly 4× signal improvement within the linear response range relative to SWM, and an 85× improvement over CM. The signal-to-noise ratio of BWM and SWM exhibits an order-of-magnitude enhancement on average compared to CM. Furthermore, we experimentally determine a minimum OPD resolution of 3.1×10-4nm, corresponding to a time delay of 1 ×10-3attoseconds and a phase shift of 3.0× 10-6rad. These results highlight the potential of weak measurement protocols for high-precision longitudinal phase estimation using narrow-band sources and common optical components.

•Mar 26, 2026•0 citations
Weak value amplification has been applied to various small physical quantities estimation, however there still lacks a practical feasible protocol to amplify ultra-small longitudinal phase, which is of importance in high precision measurement. Very recently, a different amplification protocol within the framework of weak measurements is proposed to solve this problem, which is capable of measuring any ultra-small longitudinal phase signal that conventional interferometry tries to do. Here we experimentally demonstrate this weak measurements amplification protocol of ultra-small longitudinal phase and realize one order of magnitude amplification in the same technical condition, which verifies the validity of the protocol and show higher precision and sensitivity than conventional interferometry. Our results significantly broaden the area of applications of weak measurements and may play an important role in high precision measurements.
Weak measurement amplification, which is considered as a very promising scheme in precision measurement, has been applied to various small physical quantities estimation. Since many quantities can be converted to phase signal, it is thus interesting and important to consider measuring ultra-small longitudinal phase shifts by using weak measurement. Here, we propose and experimentally demonstrate a novel weak measurement amplification based ultra-small longitudinal phase estimation, which is suitable for polarization interferometry. We realize one order of magnitude amplification measurement of small phase signal directly introduced by Liquid Crystal Variable Retarder and show its robust to finite visibility of interference. Our results may find important applications in high-precision measurements, such as gravitational waves detection.
Weak measurement amplification, which is considered as a very promising scheme in precision measurement, has been applied to various small physical quantities estimations. Since many physical quantities can be converted into phase signals, it is interesting and important to consider measuring small longitudinal phase shifts by using weak measurement. Here, we propose and experimentally demonstrate a novel weak measurement amplification-based small longitudinal phase estimation, which is suitable for polarization interferometry. We realize one order of magnitude amplification measurement of a small phase signal directly introduced by a liquid crystal variable retarder and show that it is robust to the imperfection of interference. Besides, we analyze the effect of magnification error which is never considered in the previous works, and find the constraint on the magnification. Our results may find important applications in high-precision measurements, e.g., gravitational wave detection.
Achieving higher sensitivity is an earnest purpose for precision metrology. As a response to this goal, the weak-value amplification approach has been developed for measuring ultrasmall physical effects, realizing sensitivity that had never been reached before. Encouraged by the successes, many efforts have been devoted to obtain ultimate sensitivity of weak-value amplification. However, the benefit would be easily compromised in practice, because the cost of significant reduction on signal intensity leads to an ultralow signal-to-noise ratio. In this work, we bridge this gap by proposing an alternative weak-value amplification approach, which provides sensitivity several orders of magnitude higher than the standard approach while being compatible with practical imperfections. In the proof-of-principle experiment of measuring longitudinal phase change in time domain, sensitivity up to $5\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}4}$ attosecond is exemplified. Our approach can be applied to measure other small parameters with extremely high sensitivity, providing a method for future precision metrology.
How to realize the detection of tiny birefringence is an important but challenging issue for investigations and applications in optics. In weak measurements, weak-value amplification has been widely applied to the precise estimation of time delay. Here, we show that the linear amplification in weak measurements has the potential to outperform standard weak-value amplification for ultra-small parameter characterization. The higher measurement accuracy in the linear amplification enables us to achieve a measurement of stress-induced birefringence with a high resolution of 5×10−10. Compared with existing methods, the accuracy based on weak measurements for birefringence detection can improve two orders of magnitude. Our method may have important applications in a variety of fields involving the precise measurement of time delay or birefringence.
We experimentally demonstrate an ultra-sensitive technique for measuring sub-nanometer optical path differences (OPDs) using the biased weak measurement (BWM) protocol. By employing real weak values with a classical coherent light source and introducing a bias phase procedure, this method directly amplifies small OPDs in interferometry, achieving significantly enhanced amplification compared to conventional measurement (CM) and standard weak measurement (SWM). In a proof-of-principle experiment of sub-nanometer OPD measurement, BWM achieves nearly 4× signal improvement within the linear response range relative to SWM, and an 85× improvement over CM. The signal-to-noise ratio of BWM and SWM exhibits an order-of-magnitude enhancement on average compared to CM. Furthermore, we experimentally determine a minimum OPD resolution of 3.1×10-4nm, corresponding to a time delay of 1 ×10-3attoseconds and a phase shift of 3.0× 10-6rad. These results highlight the potential of weak measurement protocols for high-precision longitudinal phase estimation using narrow-band sources and common optical components.
We experimentally demonstrate an ultra-sensitive technique for measuring sub-nanometer optical path differences (OPDs) using the biased weak measurement (BWM) protocol. By employing real weak values with a classical coherent light source and introducing a bias phase procedure, this method directly amplifies small OPDs in interferometry, achieving significantly enhanced amplification compared to conventional measurement (CM) and standard weak measurement (SWM). In a proof-of-principle experiment of sub-nanometer OPD measurement, BWM achieves nearly 4× signal improvement within the linear response range relative to SWM, and an 85× improvement over CM. The signal-to-noise ratio of BWM and SWM exhibits an order-of-magnitude enhancement on average compared to CM. Furthermore, we experimentally determine a minimum OPD resolution of 3.1×10-4nm, corresponding to a time delay of 1 ×10-3attoseconds and a phase shift of 3.0× 10-6rad. These results highlight the potential of weak measurement protocols for high-precision longitudinal phase estimation using narrow-band sources and common optical components.