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

Scientific Reports

Intensity-difference squeezing from four-wave mixing in hot 85Rb and 87Rb atoms in single diode laser pumping system

Gisung Sim, Heewoo Kim, Han Seb Moon

Published Mar 5, 2025• 7 citations
Publisher

Abstract

Abstract Squeezed states of light, generated through four-wave mixing (FWM), are increasingly recognized as valuable resources for various applications in quantum sensing, quantum imaging, and quantum information processing. In this study, we report achieving more than − 7.8 dB of intensity-difference squeezing (IDS) in two-mode squeezed states from hot 85Rb vapor and − 5.0 dB from hot 87Rb vapor, utilizing a fiber electro-optic modulator (EOM) within a single home-made diode laser system. By mitigating the effects of undesired multimode from the EOM on the squeezing, we experimentally demonstrated the IDS of 85Rb and 87Rb atoms within a single experimental setup, benefiting from the EOM's ability to provide higher frequency shifts. This advancement may expand the scope of applications for hot atomic-vapor-based quantum technologies, leveraging the capabilities of the EOM.

DOI
10.1038/s41598-025-86479-w

Related papers

Generation of tripartite squeezed state by cascaded four-wave mixing in single hot rubidium atomic system

Changbiao Li, Yufeng Li, Wei Li +4 more

Abstract We report the quantum correlated triple beams via cascaded four-wave mixing (CFWM) amplified in single hot atomic vapor. Experimentally, we show that strong quantum correlation of three light beams, among them any two’s quantum correlation is characterized by the maximum value of intensity-difference squeezing (IDS) about −7.8 ± 0.3 dB. We found there is IDS between two idler beams, because two pairs of Einstein–Podolsky–Rosen injections potentially exist in our system. Besides, CFWM can emit three-mode beams at three different frequencies, in which these beams can be well separated in the spatial domain. Moreover, much difference with other methods, the injecting probe field can manipulate the gain and IDS of output three-mode light beams, which is resulting from competition relationship between cascaded two four-wave mixing processes. More interestingly, Autler–Townes splitting of gain peaks of output signals due to dressing effect of pumping fields, will lead to the evolution of measured two- and three-mode IDS from single-mode to multi-mode at frequency domain. This result will provide a multimode quantum resource which can potentially realize multimode entanglement and quantum networks.

New Journal of Physics•Aug 30, 2022•11 citations

Compact diode-laser-pumped quantum light source based on four-wave mixing in hot rubidium vapor

Zhongzhong Qin, Jietai Jing, Jun Zhou +4 more

Using a nondegenerate four-wave mixing process in hot rubidium vapor, we demonstrate a compact diode-laser-pumped system for the generation of intensity-difference squeezing down to 8 kHz with a maximum squeezing of -7 dB. To the best of our knowledge, this is the first demonstration of kilohertz-level intensity-difference squeezing using a semiconductor laser as the pump source. This scheme is of interest for experiments involving atomic ensembles, quantum communications, and precision measurements. The diode-laser-pumped system would extend the range of possible applications for squeezing due to its low cost, ease of operation, and ease of integration.

Optics Letters•Jul 21, 2012•57 citations

Enhanced intensity-difference squeezing via energy-level modulations in hot atomic media

Da Zhang, Changbiao Li, Zhaoyang Zhang +3 more

Narrow-band intensity-difference squeezing (IDS) beams have important applications in quantum metrology and gravitational wave detection. The best way to generate narrow-band IDS is to employ a parametrically amplified (PA) four-wave mixing (FWM) process in high-gain atomic media. Such IDS can be further enhanced by cascading multiple PA FWM processes in separate atomic media. The complicated experimental setup, added losses, and mechanical stability can limit the wide use of such a scheme in practical applications. Here we show that by modulating the internal energy level(s) with an additional laser (or lasers), the degree of original IDS can be substantially increased. With an initial IDS of $(\ensuremath{-}3.6\ifmmode\pm\else\textpm\fi{}0.4)$ dB using a PA nondegenerate FWM process in a three-level $\mathrm{\ensuremath{\Lambda}}$-type configuration, the degree of IDS can be enhanced to $(\ensuremath{-}7.0\ifmmode\pm\else\textpm\fi{}0.4)$ dB or $(\ensuremath{-}9.0\ifmmode\pm\else\textpm\fi{}0.4)$ dB when we use one (two) laser beam (beams) to modulate the involved ground (excited) state (states). Our results show a low-loss, robust, and efficient way to produce a high degree of IDS and facilitate its potential applications.

arXiv:1611.05946•Physical Review A•Oct 18, 2017•65 citations

Enhanced squeezing of four-wave mixing by phase-sensitive dressed effect in a hot atomic system

Changbiao Li, Wei Li, Da Zhang +4 more

Abstract In this paper, we demonstrate that the intensity difference squeezing (IDS) of parametric amplified four-wave mixing (PA-FWM) can be modulated by the phase-sensitive dressed effect in a hot rubidium (Rb) atomic system. The introduction of phase-sensitive dressed effect can enhance the degree of IDS of PA-FWM to −8.1 dB, as compared to that in the phase-insensitive dressed PA-FWM of −6.6 dB. The phase-sensitive dressing field can not only enhance the degree of IDS of PA-FWM by the dressed effect, but can also be treated as the seed beam of the PA-six wave mixing process. So, double-injected three-mode IDS obviously has a bigger degree of IDS compared with the single-injection case. One advantage of the current scheme for enhancing the generated IDS is that the experimental setup is simple and mechanically stable. These outcomes can be used in the fabrication of quantum devices and the realization of quantum metrology.

Laser Physics Letters•Dec 20, 2019•5 citations

Greatly enhanced intensity-difference squeezing via energy-level modulations in hot atomic media

Da Zhang, Changbiao Li, Zhaoyang Zhang +3 more

Narrow-band intensity-difference squeezing (IDS) beams have important applications in quantum metrology and quantum information. The best way to generate narrow-band IDS is to employ parametrically-amplified (PA) four-wave mixing (FWM) process in high-gain atomic media. Such IDS can be further enhanced by cascading multiple PA-FWM processes in separate atomic media. The complicated experimental setup, added losses and mechanical stability can limit the wide uses of such scheme in practical applications. Here, we show that by modulating/dressing the internal energy level(s) with additional laser(s), the degree of original IDS can be substantially increased. With an initial IDS of $-4.0\pm0.1$ dB using PA-non-degenerate-FWM process in a three-level $\Lambda$-type configuration, the degree of IDS can be enhanced to $-7.0\pm0.1$ dB/$-8.1\pm0.1$ dB when we use one/two laser beam(s) to modulate the involved ground/excited state(s). Our results show a low-loss, robust and efficient way to produce high degree of IDS and facilitate its potential applications.

•Nov 18, 2016•1 citation

Ultra Compact low cost two mode squeezed light source

Shahar Monsa, Shmuel Sternklar, Eliran Talker

Quantum-correlated states of light, such as squeezed states, constitute a fundamental resource for quantum technologies, enabling enhanced performance in quantum metrology, quantum information processing, and quantum communications. The practical deployment of such technologies requires squeezed-light sources that are compact, efficient, low-cost, and robust. Here we report a compact narrowband source of two-mode squeezed light at 795 nm based on four-wave mixing in hot 85Rb atomic vapor. The source is implemented in a small, modular architecture featuring a single fiber-coupled input, an electro-optic phase modulator combined with a single Fabry-Perot etalon for probe generation, and two free-space output modes corresponding to the signal and conjugate fields. Optimized for low pump power, the system achieves up to -8 dB of intensity-difference squeezing at an analysis frequency of 0.8 MHz with a pump power of only 300 mW. The intrinsic narrowband character of the generated quantum states makes this source particularly well suited for atomic-based quantum sensing and quantum networking, including interfaces with atomic quantum memories. Our results establish a versatile and portable platform for low-SWaP squeezed-light generation, paving the way toward deployable quantum-enhanced technologies.

quant-pharXiv:2601.13939•Jan 21, 2026•0 citations
Abstract Squeezed states of light, generated through four-wave mixing (FWM), are increasingly recognized as valuable resources for various applications in quantum sensing, quantum imaging, and quantum information processing. In this study, we report achieving more than − 7.8 dB of intensity-difference squeezing (IDS) in two-mode squeezed states from hot 85Rb vapor and − 5.0 dB from hot 87Rb vapor, utilizing a fiber electro-optic modulator (EOM) within a single home-made diode laser system. By mitigating the effects of undesired multimode from the EOM on the squeezing, we experimentally demonstrated the IDS of 85Rb and 87Rb atoms within a single experimental setup, benefiting from the EOM's ability to provide higher frequency shifts. This advancement may expand the scope of applications for hot atomic-vapor-based quantum technologies, leveraging the capabilities of the EOM.
Abstract We report the quantum correlated triple beams via cascaded four-wave mixing (CFWM) amplified in single hot atomic vapor. Experimentally, we show that strong quantum correlation of three light beams, among them any two’s quantum correlation is characterized by the maximum value of intensity-difference squeezing (IDS) about −7.8 ± 0.3 dB. We found there is IDS between two idler beams, because two pairs of Einstein–Podolsky–Rosen injections potentially exist in our system. Besides, CFWM can emit three-mode beams at three different frequencies, in which these beams can be well separated in the spatial domain. Moreover, much difference with other methods, the injecting probe field can manipulate the gain and IDS of output three-mode light beams, which is resulting from competition relationship between cascaded two four-wave mixing processes. More interestingly, Autler–Townes splitting of gain peaks of output signals due to dressing effect of pumping fields, will lead to the evolution of measured two- and three-mode IDS from single-mode to multi-mode at frequency domain. This result will provide a multimode quantum resource which can potentially realize multimode entanglement and quantum networks.
Using a nondegenerate four-wave mixing process in hot rubidium vapor, we demonstrate a compact diode-laser-pumped system for the generation of intensity-difference squeezing down to 8 kHz with a maximum squeezing of -7 dB. To the best of our knowledge, this is the first demonstration of kilohertz-level intensity-difference squeezing using a semiconductor laser as the pump source. This scheme is of interest for experiments involving atomic ensembles, quantum communications, and precision measurements. The diode-laser-pumped system would extend the range of possible applications for squeezing due to its low cost, ease of operation, and ease of integration.
Narrow-band intensity-difference squeezing (IDS) beams have important applications in quantum metrology and gravitational wave detection. The best way to generate narrow-band IDS is to employ a parametrically amplified (PA) four-wave mixing (FWM) process in high-gain atomic media. Such IDS can be further enhanced by cascading multiple PA FWM processes in separate atomic media. The complicated experimental setup, added losses, and mechanical stability can limit the wide use of such a scheme in practical applications. Here we show that by modulating the internal energy level(s) with an additional laser (or lasers), the degree of original IDS can be substantially increased. With an initial IDS of $(\ensuremath{-}3.6\ifmmode\pm\else\textpm\fi{}0.4)$ dB using a PA nondegenerate FWM process in a three-level $\mathrm{\ensuremath{\Lambda}}$-type configuration, the degree of IDS can be enhanced to $(\ensuremath{-}7.0\ifmmode\pm\else\textpm\fi{}0.4)$ dB or $(\ensuremath{-}9.0\ifmmode\pm\else\textpm\fi{}0.4)$ dB when we use one (two) laser beam (beams) to modulate the involved ground (excited) state (states). Our results show a low-loss, robust, and efficient way to produce a high degree of IDS and facilitate its potential applications.
Abstract In this paper, we demonstrate that the intensity difference squeezing (IDS) of parametric amplified four-wave mixing (PA-FWM) can be modulated by the phase-sensitive dressed effect in a hot rubidium (Rb) atomic system. The introduction of phase-sensitive dressed effect can enhance the degree of IDS of PA-FWM to −8.1 dB, as compared to that in the phase-insensitive dressed PA-FWM of −6.6 dB. The phase-sensitive dressing field can not only enhance the degree of IDS of PA-FWM by the dressed effect, but can also be treated as the seed beam of the PA-six wave mixing process. So, double-injected three-mode IDS obviously has a bigger degree of IDS compared with the single-injection case. One advantage of the current scheme for enhancing the generated IDS is that the experimental setup is simple and mechanically stable. These outcomes can be used in the fabrication of quantum devices and the realization of quantum metrology.
Narrow-band intensity-difference squeezing (IDS) beams have important applications in quantum metrology and quantum information. The best way to generate narrow-band IDS is to employ parametrically-amplified (PA) four-wave mixing (FWM) process in high-gain atomic media. Such IDS can be further enhanced by cascading multiple PA-FWM processes in separate atomic media. The complicated experimental setup, added losses and mechanical stability can limit the wide uses of such scheme in practical applications. Here, we show that by modulating/dressing the internal energy level(s) with additional laser(s), the degree of original IDS can be substantially increased. With an initial IDS of −4.0±0.1-4.0\pm0.1−4.0±0.1 dB using PA-non-degenerate-FWM process in a three-level Λ\LambdaΛ-type configuration, the degree of IDS can be enhanced to −7.0±0.1-7.0\pm0.1−7.0±0.1 dB/−8.1±0.1-8.1\pm0.1−8.1±0.1 dB when we use one/two laser beam(s) to modulate the involved ground/excited state(s). Our results show a low-loss, robust and efficient way to produce high degree of IDS and facilitate its potential applications.
Quantum-correlated states of light, such as squeezed states, constitute a fundamental resource for quantum technologies, enabling enhanced performance in quantum metrology, quantum information processing, and quantum communications. The practical deployment of such technologies requires squeezed-light sources that are compact, efficient, low-cost, and robust. Here we report a compact narrowband source of two-mode squeezed light at 795 nm based on four-wave mixing in hot 85Rb atomic vapor. The source is implemented in a small, modular architecture featuring a single fiber-coupled input, an electro-optic phase modulator combined with a single Fabry-Perot etalon for probe generation, and two free-space output modes corresponding to the signal and conjugate fields. Optimized for low pump power, the system achieves up to -8 dB of intensity-difference squeezing at an analysis frequency of 0.8 MHz with a pump power of only 300 mW. The intrinsic narrowband character of the generated quantum states makes this source particularly well suited for atomic-based quantum sensing and quantum networking, including interfaces with atomic quantum memories. Our results establish a versatile and portable platform for low-SWaP squeezed-light generation, paving the way toward deployable quantum-enhanced technologies.