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

Journal of the Optical Society of America B

Measuring orbital angular momentum of a vortex beam with atom-based structured light

Nawaz Sarif Mallick

Published Dec 17, 2024• 11 citations
Publisher

Abstract

This study presents an innovative scheme for detecting the orbital angular momentum (OAM) of vortex beams within an atomic ensemble. Leveraging a homogeneously broadened four-level atomic system driven by two orthogonal polarization probe beams, we demonstrate the selective generation of structured beams without the need for magnetic fields between the two ground states. Through detailed theoretical analysis and numerical simulations, we elucidate the phase-dependent behavior of atomic coherences induced by an OAM-carrying Laguerre–Gaussian optical probe beam. These findings enable the creation of petal-like structures within the probe beam, with the number of petals directly correlated to the OAM value. Our investigation underscores the potential of this OAM detection scheme as a highly sensitive and precise sensor, applicable across diverse domains such as telecommunication, microscopy, and optical metrology.

DOI
10.1364/josab.537012

Related papers

Vortex beam assisted generation and manipulation of structured light

Nawaz Sarif Mallick

We conduct theoretical investigations into a fundamental closed-loop Λ-type atomic system using 87 Rb atoms, aiming to efficiently generate and manipulate structured light beams. A phase-singular microwave (MW) beam with a topological charge l μ and a phase-singular optical probe beam with a topological charge l p collectively induce phase-dependent atomic coherence, resulting in periodic oscillations of probe absorption in the transverse plane. The number of absorption or transparency windows in the transverse plane is determined by the resultant topological charge of the system, denoted as l = l μ − l p . We investigate the propagation of a paraxial doughnut-shaped probe beam through the phase-dependent atomic medium and showcase the generation of petal-like structured beams for various combinations of l μ and l p . We provide a detailed theoretical explanation of these results using the analytical expression of probe susceptibility. We outline how this scheme effectively serves as a sensor adept at discerning particular OAM modes. This selective detection capability is valuable in scenarios where only certain OAM states carry relevant information. The relative phase between the interacting fields can be used to rotate the structured probe beam by 360 deg in the clockwise or counterclockwise direction. This manipulation of spatial position of different OAM modes can be employed in implementing OAM-based logical operations.

Journal of the Optical Society of America B•Aug 5, 2024•14 citations

Mapping of atoms via the coherence superpositions of orbital angular momentum light

Xingke Wu, Zhiping Wang, Benli Yu

We propose a scheme to map atoms via the coherence superpositions of orbital angular momentum (OAM) light. The atoms are prepared in the four-level tripod configuration in the presence of a vortex light, which coherently superposes two Laguerre-Gaussian (LG) beam modes with equal but opposite OAM. Because of the spatially dependent atom-field interaction, the information about the position of the atom can be obtained via the absorption measurement of the weak probe field. It is found that the absorption behavior is significantly impacted by the detuning, control field, azimuthal number, and radial number. Most importantly, atomic mapping accuracy can be controlled by properly adjusting the detunings and control field. The coherent interaction of OAM light with atoms constitutes a platform for active mapping of atoms at specific positions in azimuthal space.

Journal of the Optical Society of America B•Feb 7, 2024•7 citations

Four-wave mixing-based orbital angular momentum translation

Nawaz Sarif Mallick, Tarak Nath Dey

We theoretically study the generation of orbital angular momentum (OAM) based on the four-wave mixing process in a diamond-type homogeneously broadened 85 R b atomic system. We use density matrix formalism at a weak field limit to explain the origin of vortex translation between different optical fields and a generated signal. We show how the singularities, which are omnipresent in the phases of the input optical vortex beams, can be profoundly mapped to atomic coherence in the transverse plane, which holds the origin of OAM translation. This translation process works well even for a moderately intense probe and control field, which enhances medium nonlinearity. The generation and manipulation of OAM of the light beam in a nonlinear medium may have important applications in optical tweezers and quantum information processing systems.

arXiv:1905.02347•Journal of the Optical Society of America B•May 4, 2020•24 citations

Coherent phase control of orbital-angular-momentum light-induced torque in a double-tripod atom-light coupling scheme

Hamid R. Hamedi, Viačeslav Kudriašov, Mažena Mackoit-Sinkevičienė +1 more

We investigate a phase-controllable mechanism for generating optical torque in a five-level double-tripod (DT) atom-light coupling scheme interacting with four strong coherent control fields as well as two weak optical vortex probe beams carrying orbital angular momentum (OAM). The spatial phase gradients of the OAM-carrying probes induce a quantized torque that is transferred to the atoms, rotating them and generating a directed atomic flow within an annular geometry. Analytical solutions of the optical Bloch equations under steady-state conditions show that the induced torque and resulting rotational motion exhibit high sensitivity to phase variations. We show that the DT system coherently reconfigures into either coupled Λ or double-Λ schemes depending on the relative phases, with each configuration exhibiting distinct quantized torque characteristics. This enables precise phase control of the atomic current flow, with potential applications in quantum control, precision measurement, and quantum information processing.

quant-pharXiv:2512.17537•Physical Review A•Dec 22, 2025•1 citation

Theoretical study of spatially controlled atomic localization using hybrid Gaussian & Laguerre–Gaussian beams

Himani Thakur, Zubair Iqbal Dar, Paramjit Kaur

Abstract We study high-resolution atomic localization in a multilevel atomic system driven simultaneously by a Gaussian and a Laguerre–Gaussian (LG) beam. The coexistence of the two fields creates a hybrid coupling landscape in which the Gaussian beam supplies radial confinement, while the LG beam contributes an orbital angular momentum (OAM)-dependent azimuthal modulation. By solving the steady-state density-matrix equations, we show that the resulting localization patterns contain mixed spatial harmonics whose structure is set by the topological charge, beam waist, and probe detuning. The OAM index determines the angular symmetry of the localized absorption features, whereas the beam waist controls their radial extent. Probe detuning provides an additional tuning mechanism that alters the contrast and geometry of the localization regions. These results highlight how structured light fields can be used to engineer controllable spatial localization in atomic media, with relevance to precision metrology, spatially resolved quantum control, and structured-light sensing.

Physica Scripta•Apr 9, 2026•0 citations

Azimuthal modulation of electromagnetically induced transparency using structured light

Hamid Reza Hamedi, Viačeslav Kudriašov, Julius Ruseckas +1 more

Recently a scheme has been proposed for detection of the structured light by measuring the transmission of a vortex beam through a cloud of cold rubidium atoms with energy levels of the Λ-type configuration [N. Radwell et al., Phys. Rev. Lett.114, 123603 (2015) ]. This enables observation of regions of spatially dependent electromagnetically induced transparency (EIT). Here we suggest another scenario for detection of the structured light by measuring the absorption profile of a weak nonvortex probe beam in a highly resonant five-level combined tripod and Λ (CTL) atom-light coupling setup. We demonstrate that due to the closed-loop structure of CTL scheme, the absorption of the probe beam depends on the azimuthal angle and orbital angular momentum (OAM) of the control vortex beams. This feature is missing in simple Λ or tripod schemes, as there is no loop in such atom-light couplings. One can identify different regions of spatially structured transparency through measuring the absorption of probe field under different configurations of structured control light.

arXiv:1807.01803•Optics Express•Oct 15, 2018•97 citations
This study presents an innovative scheme for detecting the orbital angular momentum (OAM) of vortex beams within an atomic ensemble. Leveraging a homogeneously broadened four-level atomic system driven by two orthogonal polarization probe beams, we demonstrate the selective generation of structured beams without the need for magnetic fields between the two ground states. Through detailed theoretical analysis and numerical simulations, we elucidate the phase-dependent behavior of atomic coherences induced by an OAM-carrying Laguerre–Gaussian optical probe beam. These findings enable the creation of petal-like structures within the probe beam, with the number of petals directly correlated to the OAM value. Our investigation underscores the potential of this OAM detection scheme as a highly sensitive and precise sensor, applicable across diverse domains such as telecommunication, microscopy, and optical metrology.
We conduct theoretical investigations into a fundamental closed-loop Λ-type atomic system using 87 Rb atoms, aiming to efficiently generate and manipulate structured light beams. A phase-singular microwave (MW) beam with a topological charge l μ and a phase-singular optical probe beam with a topological charge l p collectively induce phase-dependent atomic coherence, resulting in periodic oscillations of probe absorption in the transverse plane. The number of absorption or transparency windows in the transverse plane is determined by the resultant topological charge of the system, denoted as l = l μ − l p . We investigate the propagation of a paraxial doughnut-shaped probe beam through the phase-dependent atomic medium and showcase the generation of petal-like structured beams for various combinations of l μ and l p . We provide a detailed theoretical explanation of these results using the analytical expression of probe susceptibility. We outline how this scheme effectively serves as a sensor adept at discerning particular OAM modes. This selective detection capability is valuable in scenarios where only certain OAM states carry relevant information. The relative phase between the interacting fields can be used to rotate the structured probe beam by 360 deg in the clockwise or counterclockwise direction. This manipulation of spatial position of different OAM modes can be employed in implementing OAM-based logical operations.
We propose a scheme to map atoms via the coherence superpositions of orbital angular momentum (OAM) light. The atoms are prepared in the four-level tripod configuration in the presence of a vortex light, which coherently superposes two Laguerre-Gaussian (LG) beam modes with equal but opposite OAM. Because of the spatially dependent atom-field interaction, the information about the position of the atom can be obtained via the absorption measurement of the weak probe field. It is found that the absorption behavior is significantly impacted by the detuning, control field, azimuthal number, and radial number. Most importantly, atomic mapping accuracy can be controlled by properly adjusting the detunings and control field. The coherent interaction of OAM light with atoms constitutes a platform for active mapping of atoms at specific positions in azimuthal space.
We theoretically study the generation of orbital angular momentum (OAM) based on the four-wave mixing process in a diamond-type homogeneously broadened 85 R b atomic system. We use density matrix formalism at a weak field limit to explain the origin of vortex translation between different optical fields and a generated signal. We show how the singularities, which are omnipresent in the phases of the input optical vortex beams, can be profoundly mapped to atomic coherence in the transverse plane, which holds the origin of OAM translation. This translation process works well even for a moderately intense probe and control field, which enhances medium nonlinearity. The generation and manipulation of OAM of the light beam in a nonlinear medium may have important applications in optical tweezers and quantum information processing systems.
We investigate a phase-controllable mechanism for generating optical torque in a five-level double-tripod (DT) atom-light coupling scheme interacting with four strong coherent control fields as well as two weak optical vortex probe beams carrying orbital angular momentum (OAM). The spatial phase gradients of the OAM-carrying probes induce a quantized torque that is transferred to the atoms, rotating them and generating a directed atomic flow within an annular geometry. Analytical solutions of the optical Bloch equations under steady-state conditions show that the induced torque and resulting rotational motion exhibit high sensitivity to phase variations. We show that the DT system coherently reconfigures into either coupled Λ or double-Λ schemes depending on the relative phases, with each configuration exhibiting distinct quantized torque characteristics. This enables precise phase control of the atomic current flow, with potential applications in quantum control, precision measurement, and quantum information processing.
Abstract We study high-resolution atomic localization in a multilevel atomic system driven simultaneously by a Gaussian and a Laguerre–Gaussian (LG) beam. The coexistence of the two fields creates a hybrid coupling landscape in which the Gaussian beam supplies radial confinement, while the LG beam contributes an orbital angular momentum (OAM)-dependent azimuthal modulation. By solving the steady-state density-matrix equations, we show that the resulting localization patterns contain mixed spatial harmonics whose structure is set by the topological charge, beam waist, and probe detuning. The OAM index determines the angular symmetry of the localized absorption features, whereas the beam waist controls their radial extent. Probe detuning provides an additional tuning mechanism that alters the contrast and geometry of the localization regions. These results highlight how structured light fields can be used to engineer controllable spatial localization in atomic media, with relevance to precision metrology, spatially resolved quantum control, and structured-light sensing.
Recently a scheme has been proposed for detection of the structured light by measuring the transmission of a vortex beam through a cloud of cold rubidium atoms with energy levels of the Λ-type configuration [N. Radwell et al., Phys. Rev. Lett.114, 123603 (2015) ]. This enables observation of regions of spatially dependent electromagnetically induced transparency (EIT). Here we suggest another scenario for detection of the structured light by measuring the absorption profile of a weak nonvortex probe beam in a highly resonant five-level combined tripod and Λ (CTL) atom-light coupling setup. We demonstrate that due to the closed-loop structure of CTL scheme, the absorption of the probe beam depends on the azimuthal angle and orbital angular momentum (OAM) of the control vortex beams. This feature is missing in simple Λ or tripod schemes, as there is no loop in such atom-light couplings. One can identify different regions of spatially structured transparency through measuring the absorption of probe field under different configurations of structured control light.