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

AIP Advances

Modulation of the optical beam with orbital angular momentum in hot atomic rubidium vapor

Lei Zeng, Ming‐Xin Dong, Ying-Hao Ye, Yichen Yu, Enze Li, Weihang Zhang, Kan Zhang, Dong-Sheng Ding, Bao-Sen Shi

Published Jan 1, 2020• 3 citations
Publisher

Abstract

The effect of self-focusing and defocusing of the optical beam, which is caused by the interaction between a strong light field and medium, plays an important role in nonlinear optics. The difference in the spatial structure of the strong control beam with orbital angular momentum (OAM) and the Gaussian mode will have different effects on self-focusing and defocusing, which has the potential for realizing the modulation of the self-focusing and the defocusing process of the probe light with OAM. In this work, we report the influence of the spatial structure of the control beam on the self-focusing and defocusing process of the probe beam in a hot rubidium vapor cell with a lambda-type configuration. Under the same experimental condition, the control beam with the Laguerre-Gaussian mode contributes more to self-defocusing, while the Gaussian mode promotes the defocusing effect. The result is promising for manipulating the optical beam with OAM.

DOI
10.1063/1.5131179

Related papers

Identification of orbital angular momentum using atom-based spatial self-phase modulation

Wei Gao, Sandan Wang, Jinpeng Yuan +3 more

Optical vortex orbital angular momentum modes, namely the twists number of the light does in one wavelength, play a critical role in quantum-information coding, super-resolution imaging, and high-precision optical measurement. Here, we present the identification of the orbital angular momentum modes based on spatial self-phase modulation in rubidium atomic vapor. The refractive index of atomic medium is spatially modulated by the focused vortex laser beam, and the resulted nonlinear phase shift of beam directly related to the orbital angular momentum modes. The output diffraction pattern carries clearly distinguishable tails, whose number and rotation direction correspond to the magnitude and sign of the input beam orbital angular momentum, respectively. Furthermore, the visualization degree of orbital angular momentums identification is adjusted on-demand in the terms of incident power and frequency detuning. These results show that the spatial self-phase modulation of atomic vapor can provide a feasible and effective way to rapidly readout the orbital angular momentum modes of vortex beam.

Optics Express•Mar 24, 2023•9 citations

Four-Wave Mixing with Orbital Angular Momentum Transfer

Hana Warner

We explore the conservation of orbital angular momentum (OAM) in the four-wave mixing (FWM) process in hot rubidium vapor. Since most modern communication systems send data in pulses corresponding to bits, we can use OAM to encode more information in each pulse by assigning structure to each signal. Furthermore, because FWM can be used to generate entangled photon pairs, we can use this process to bring enhanced signal security. We experimentally studied FWM with a wide range of Laguerre-Gaussian modes and their superpositions and observed OAM transfer from the probe field to a generated Stokes field. By studying the output Stokes intensity and phase distributions, we confirm l mode (OAM) conservation for pure l and p modes, as well as for the superpositions of l and -l for the mode numbers up to l = 4, p = 4. We also found that p index is generally not conserved and its conservation is highly dependent on the relative sizes of the probe and pump beams in the Rb cell. We also identify parameters to improve FWM gain with OAM transfer and propose an analytical method for determining OAM p number.

•Jan 1, 2020•0 citations

Inter-frequency all-optical transfer of structured light information in Rb vapor based on spatial cross-phase modulation

Junfei Chen, Zhiping Wang, Hamid Reza Hamedi +1 more

High-dimensional all-optical information transfer facilitates large-capacity, high-speed, and energy-efficient optical communication, playing a pivotal role in advancing modern photonic technologies. Here, we demonstrate the all-optical transfer of structured information between two beams with different frequencies via spatial cross-phase modulation in a hot 85Rb vapor. A high-power pump beam, characterized by a structured light, induces a refractive index change in the rubidium vapor. A low-power, initially Gaussian probe beam counter-propagates through the rubidium vapor cell, undergoing a nonlinear phase shift induced by the pump beam. This enables the transfer of the spatial characteristics imprinted by the pump beam onto the probe beam with maximum structural integrity and similarity. The spatial evolution of the transverse intensity of the probe beam vs frequency detunings of the pump and probe beams, pump beam power, and cell temperature is studied. We have further shown that the structural similarity can be manipulated by changing the pump beam power and temperature of the vapor cell. Our findings may reveal a way to manipulate light fields, offering potential applications in optical communication, all-optical data processing, and advanced photonic devices.

Applied Physics Letters•Apr 14, 2025•1 citation

Manipulation of the orbital angular momentum via four-wave mixing in Rb vapor

Ning Liu, Xuewen Wang, Jinpeng Yuan +3 more

Abstract The manipulation of the orbital angular momentum (OAM) contributes to understand the OAM multiplexing, is significant in free-space optical communication and information processing. We theoretically simulate and experimentally demonstrate the regularity of the OAM transfer, including the angular and radial modes, of Laguerre–Gaussian beam via four-wave mixing process in 85Rb vapor. The 420 nm coherent blue light output field inherits the phase characteristic of 780 nm and 776 nm beams with different OAM modes. The output field OAM modes show the transfer as a typical arithmetic operation of the input field OAM modes with equal-handed angular indice l, while, the conversion between angular and radial modes occurs with the opposite angular indice l. Such rules of the OAM transfer and manipulation have implications on the research of high-capacity information transfer and quantum communication.

Laser Physics Letters•Jan 31, 2023•6 citations

Two-Mode Squeezing and Conservation of Optical Angular Momentum via Four-Wave Mixing in Rubidium

Nathan Super

The goal of the project is to produce a pair of intensity-squeezed light fields using Four-Wave Mixing (FWM) in hot Rubidium vapor. In this process, interaction of atoms with near-resonant strong control optical field results in strong amplification of a weak probe optical field and in generation of a quantum correlated conjugate Stokes optical field. In order to establish the quantum correlation between the Stokes and probe fields, we measured the differential intensity noise between the Stokes and probe fields. If the noise falls below the quantum noise limit, then two-mode intensity squeezing has been achieved, as a first step toward realization of the polarization Bell states. We also examine the conservation of orbital angular momentum (OAM) in the FWM process with OAM-bearing input fields.

•Jan 1, 2018•0 citations

Modulation of spatial Raman gain induced by Laguerre–Gaussian vortex beams

Qi MING, Zhenxing Fu

(1), 013701, which focused on overall optical gain in open-loop configurations, our study examines how structured light modulates the spatial distribution of Raman gain. Using a density-matrix approach, we numerically obtain two-dimensional maps and cross-sectional profiles of Raman gain. The results show that three parameters-the orbital angular momentum (OAM) of the LG beam, the single-photon detuning, and the relative phase of the control fields-collectively determine the spatial morphology of the gain. OAM controls the transition between single-lobe and multi-lobe structures, modulates the gain magnitude and spatial complexity, and the relative phase induces rotational or mirror-symmetric transformations. This work provides the first systematic analysis of spatial Raman-gain modulation in a closed-loop three-level system, demonstrating the strong capability of structured light to tailor nonlinear gain processes. The findings extend the theoretical framework beyond PRA 2024 and offer insights for spatially selective amplification and structured-light-based photonic device design.

Physical Chemistry Chemical Physics•Jan 1, 2026•0 citations
The effect of self-focusing and defocusing of the optical beam, which is caused by the interaction between a strong light field and medium, plays an important role in nonlinear optics. The difference in the spatial structure of the strong control beam with orbital angular momentum (OAM) and the Gaussian mode will have different effects on self-focusing and defocusing, which has the potential for realizing the modulation of the self-focusing and the defocusing process of the probe light with OAM. In this work, we report the influence of the spatial structure of the control beam on the self-focusing and defocusing process of the probe beam in a hot rubidium vapor cell with a lambda-type configuration. Under the same experimental condition, the control beam with the Laguerre-Gaussian mode contributes more to self-defocusing, while the Gaussian mode promotes the defocusing effect. The result is promising for manipulating the optical beam with OAM.
Optical vortex orbital angular momentum modes, namely the twists number of the light does in one wavelength, play a critical role in quantum-information coding, super-resolution imaging, and high-precision optical measurement. Here, we present the identification of the orbital angular momentum modes based on spatial self-phase modulation in rubidium atomic vapor. The refractive index of atomic medium is spatially modulated by the focused vortex laser beam, and the resulted nonlinear phase shift of beam directly related to the orbital angular momentum modes. The output diffraction pattern carries clearly distinguishable tails, whose number and rotation direction correspond to the magnitude and sign of the input beam orbital angular momentum, respectively. Furthermore, the visualization degree of orbital angular momentums identification is adjusted on-demand in the terms of incident power and frequency detuning. These results show that the spatial self-phase modulation of atomic vapor can provide a feasible and effective way to rapidly readout the orbital angular momentum modes of vortex beam.
We explore the conservation of orbital angular momentum (OAM) in the four-wave mixing (FWM) process in hot rubidium vapor. Since most modern communication systems send data in pulses corresponding to bits, we can use OAM to encode more information in each pulse by assigning structure to each signal. Furthermore, because FWM can be used to generate entangled photon pairs, we can use this process to bring enhanced signal security. We experimentally studied FWM with a wide range of Laguerre-Gaussian modes and their superpositions and observed OAM transfer from the probe field to a generated Stokes field. By studying the output Stokes intensity and phase distributions, we confirm l mode (OAM) conservation for pure l and p modes, as well as for the superpositions of l and -l for the mode numbers up to l = 4, p = 4. We also found that p index is generally not conserved and its conservation is highly dependent on the relative sizes of the probe and pump beams in the Rb cell. We also identify parameters to improve FWM gain with OAM transfer and propose an analytical method for determining OAM p number.
High-dimensional all-optical information transfer facilitates large-capacity, high-speed, and energy-efficient optical communication, playing a pivotal role in advancing modern photonic technologies. Here, we demonstrate the all-optical transfer of structured information between two beams with different frequencies via spatial cross-phase modulation in a hot 85Rb vapor. A high-power pump beam, characterized by a structured light, induces a refractive index change in the rubidium vapor. A low-power, initially Gaussian probe beam counter-propagates through the rubidium vapor cell, undergoing a nonlinear phase shift induced by the pump beam. This enables the transfer of the spatial characteristics imprinted by the pump beam onto the probe beam with maximum structural integrity and similarity. The spatial evolution of the transverse intensity of the probe beam vs frequency detunings of the pump and probe beams, pump beam power, and cell temperature is studied. We have further shown that the structural similarity can be manipulated by changing the pump beam power and temperature of the vapor cell. Our findings may reveal a way to manipulate light fields, offering potential applications in optical communication, all-optical data processing, and advanced photonic devices.
Abstract The manipulation of the orbital angular momentum (OAM) contributes to understand the OAM multiplexing, is significant in free-space optical communication and information processing. We theoretically simulate and experimentally demonstrate the regularity of the OAM transfer, including the angular and radial modes, of Laguerre–Gaussian beam via four-wave mixing process in 85Rb vapor. The 420 nm coherent blue light output field inherits the phase characteristic of 780 nm and 776 nm beams with different OAM modes. The output field OAM modes show the transfer as a typical arithmetic operation of the input field OAM modes with equal-handed angular indice l, while, the conversion between angular and radial modes occurs with the opposite angular indice l. Such rules of the OAM transfer and manipulation have implications on the research of high-capacity information transfer and quantum communication.
The goal of the project is to produce a pair of intensity-squeezed light fields using Four-Wave Mixing (FWM) in hot Rubidium vapor. In this process, interaction of atoms with near-resonant strong control optical field results in strong amplification of a weak probe optical field and in generation of a quantum correlated conjugate Stokes optical field. In order to establish the quantum correlation between the Stokes and probe fields, we measured the differential intensity noise between the Stokes and probe fields. If the noise falls below the quantum noise limit, then two-mode intensity squeezing has been achieved, as a first step toward realization of the polarization Bell states. We also examine the conservation of orbital angular momentum (OAM) in the FWM process with OAM-bearing input fields.
(1), 013701, which focused on overall optical gain in open-loop configurations, our study examines how structured light modulates the spatial distribution of Raman gain. Using a density-matrix approach, we numerically obtain two-dimensional maps and cross-sectional profiles of Raman gain. The results show that three parameters-the orbital angular momentum (OAM) of the LG beam, the single-photon detuning, and the relative phase of the control fields-collectively determine the spatial morphology of the gain. OAM controls the transition between single-lobe and multi-lobe structures, modulates the gain magnitude and spatial complexity, and the relative phase induces rotational or mirror-symmetric transformations. This work provides the first systematic analysis of spatial Raman-gain modulation in a closed-loop three-level system, demonstrating the strong capability of structured light to tailor nonlinear gain processes. The findings extend the theoretical framework beyond PRA 2024 and offer insights for spatially selective amplification and structured-light-based photonic device design.