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

Optics Letters

On the quantum-channel capacity for orbital angular momentum-based free-space optical communications

Yequn Zhang, Ivan B. Djordjević, Xin Gao

Published Jul 30, 2012• 26 citations
Publisher

Abstract

Inspired by recent demonstrations of orbital angular momentum-(OAM)-based single-photon communications, we propose two quantum-channel models: (i) the multidimensional quantum-key distribution model and (ii) the quantum teleportation model. Both models employ operator-sum representation for Kraus operators derived from OAM eigenkets transition probabilities. These models are highly important for future development of quantum-error correction schemes to extend the transmission distance and improve date rates of OAM quantum communications. By using these models, we calculate corresponding quantum-channel capacities in the presence of atmospheric turbulence.

DOI
10.1364/ol.37.003267

Related papers

Quantum channel capacity for OAM-based free-space optical communications

Ivan B. Djordjević, Yequn Zhang, Xin Gao

We study the channel capacity for orbital angular momentum (OAM) based quantum free-space optical communications. Inspired by recent demonstrations for OAM-based single-photon communication, we construct the quantum density operator in matrix form, based on OAM eigenkets, and determine the quantum channel model suitable for study of the quantum communication over atmospheric turbulence channels. The quantum channel model is derived from OAM eigenkets transition probabilities. By using this model we determine the OAM quantum channel capacity in the presence of atmospheric turbulence. The proposed quantum channel model is of high importance for future study of quantum error correction coding to extend the transmission distance and data rate of free-space quantum communications.

Proceedings of SPIE, the International Society for Optical Engineering/Proceedings of SPIE•Oct 15, 2012•4 citations

Atmospheric turbulence and free-space optical communication using orbital angular momentum of single photons

Carl Paterson

The well defined spin and orbital angular momentum states of photons offers a practical realization of quantum digits and a means of secure single-photon optical communication. The orbital angular momentum is associated with the spatial distribution of the wavefunction and the number of orbital angular momentum eigenstates is unlimited, giving the possibility of arbitrary base-N digits. In this paper, free-space optical communications using angular momentum states of single photons is investigated and in particular the effect of atmospheric turbulence on the angular momentum of the photons is modelled. The refractive index fluctuations in the atmosphere perturb the complex amplitude of a propagating beam so that the photons that were launched in an eigenstate of orbital angular momentum are no longer guaranteed to be in the original eigenstate after propagation. By considering the resulting wave as a superposition of angular momentum states, the probability of obtaining correct or incorrect measurements of the transmitted digit is calculated. The effect on a free-space optical communication using orbital angular momentum and the use of adaptive optics is discussed. The information capacity per photon is quantified and compared to that using polarization states for binary digits.

Proceedings of SPIE, the International Society for Optical Engineering/Proceedings of SPIE•Nov 11, 2004•16 citations

Influence of atmospheric turbulence on optical communications using orbital angular momentum for encoding

Mehul Malik, Malcolm N. O’Sullivan, Brandon Rodenburg +5 more

We describe an experimental implementation of a free-space 11-dimensional communication system using orbital angular momentum (OAM) modes. This system has a maximum measured OAM channel capacity of 2.12 bits/photon. The effects of Kolmogorov thin-phase turbulence on the OAM channel capacity are quantified. We find that increasing the turbulence leads to a degradation of the channel capacity. We are able to mitigate the effects of turbulence by increasing the spacing between detected OAM modes. This study has implications for high-dimensional quantum key distribution (QKD) systems. We describe the sort of QKD system that could be built using our current technology.

arXiv:1204.5781•Optics Express•May 25, 2012•332 citations

Research on the Selection of Orders for Quantum Key Distribution Protocols Based on Photon Orbital Angular Momentum Encoding in Free Space

Dong-Yi Wu, Lei Shi, Xingyu Wang +7 more

Quantum key distribution (QKD) technology has demonstrated remarkable practicality and sustained developmental trends in the current field of quantum communication. This paper focuses on a novel and potent quantum communication protocol, specifically quantum key distribution utilizing the encoding of information through orbital angular momentum (OAM) of photons. OAM states, owing to their distinctive properties, exhibit significant advantages in terms of information capacity and channel robustness. However, the sensitivity of OAM states to atmospheric conditions and challenges arising from wavefront distortions necessitate in-depth investigation. Additionally, the unique structure of OAM beams has raised concerns about geometric losses. By analyzing the impact of atmospheric turbulence and geometric losses on the transmission performance when applying the OAM-QKD protocol in free space, this paper explores variations in system losses under different OAM orders. Simulation results indicated that as the channel distance increases, system losses gradually escalate. Furthermore, with an increase in OAM order, although the system's sensitivity to atmospheric turbulence diminishes, geometric losses exhibit an exponential increase. Addressing this issue, our research suggested that when considering free-space quantum key distribution with OAM encoding, selecting an OAM order of 1 for the beam achieves minimal transmission losses. Therefore, in practical applications, employing OAM beams with <?TeX $l = 1$ ?> emerges as an effective strategy to optimize the performance of the OAM-QKD protocol in free space.

International Conference on Cryptography, Network Security and Communication Technology (CNSCT)•Jan 19, 2024•0 citations

Quantum Few-Mode Fiber Communications Based on the Orbital Angular Momentum

Changyu Lin, Ivan B. Djordjević, Milorad Cvijetić

We study a quantum few-mode fiber (FMF) communication scheme based on orbital angular momentum (OAM) modes and applied quantum information theory to develop the quantum FMF channel model and to calculate the quantum channel capacity. We assume a strong mode-coupling regime in FMF and an imperfect generation of OAM modes. The quantum FMF channel is modeled as a concatenation of many fiber sections describing the OAM eigenkets transitions as a Markov chain. The proposed model is suitable for the study of the multidimensional quantum key distribution and teleportation over FMFs. Numerical simulations are performed to demonstrate the ability of the model to determine the FMF output density state for a given input density state. It is shown that FMF quantum channel capacity decreases with distance in a strong coupling regime if OAM basekets are imperfectly generated.

IEEE Photonics Technology Letters•Oct 15, 2012•14 citations

Orbital Angular Momentum Multiplexing for Free-space Quantum Key Distribution Impaired by Turbulence

Yu Chen, Shenjie Huang, Majid Safari

In this paper, a free-space quantum key distribution (QKD) system based on BB84 protocol is studied assuming that the transmitted quantum bits are multiplexed spatially based on orthogonal orbital angular momentum (OAM) carrying beams. The performance of such a system is estimated in terms of quantum bit error rate, outage capacity, and effective data rate taking into account the impact of error correction and privacy amplification. Based on the simulation of OAM-carrying beam propagating through atmospheric channels impaired by turbulence, the crosstalk among the multiplexed channels are investigated and its effect on the performance of the QKD system is evaluated. The presented results provide insight into the efficient design of such multiplexed QKD systems particularly in terms of the choice of the optimal average photon number per pulse and the multiplexing mode set.

International Wireless Communications and Mobile Computing Conference (IWCMC)•Jun 1, 2018•6 citations
Inspired by recent demonstrations of orbital angular momentum-(OAM)-based single-photon communications, we propose two quantum-channel models: (i) the multidimensional quantum-key distribution model and (ii) the quantum teleportation model. Both models employ operator-sum representation for Kraus operators derived from OAM eigenkets transition probabilities. These models are highly important for future development of quantum-error correction schemes to extend the transmission distance and improve date rates of OAM quantum communications. By using these models, we calculate corresponding quantum-channel capacities in the presence of atmospheric turbulence.
We study the channel capacity for orbital angular momentum (OAM) based quantum free-space optical communications. Inspired by recent demonstrations for OAM-based single-photon communication, we construct the quantum density operator in matrix form, based on OAM eigenkets, and determine the quantum channel model suitable for study of the quantum communication over atmospheric turbulence channels. The quantum channel model is derived from OAM eigenkets transition probabilities. By using this model we determine the OAM quantum channel capacity in the presence of atmospheric turbulence. The proposed quantum channel model is of high importance for future study of quantum error correction coding to extend the transmission distance and data rate of free-space quantum communications.
The well defined spin and orbital angular momentum states of photons offers a practical realization of quantum digits and a means of secure single-photon optical communication. The orbital angular momentum is associated with the spatial distribution of the wavefunction and the number of orbital angular momentum eigenstates is unlimited, giving the possibility of arbitrary base-N digits. In this paper, free-space optical communications using angular momentum states of single photons is investigated and in particular the effect of atmospheric turbulence on the angular momentum of the photons is modelled. The refractive index fluctuations in the atmosphere perturb the complex amplitude of a propagating beam so that the photons that were launched in an eigenstate of orbital angular momentum are no longer guaranteed to be in the original eigenstate after propagation. By considering the resulting wave as a superposition of angular momentum states, the probability of obtaining correct or incorrect measurements of the transmitted digit is calculated. The effect on a free-space optical communication using orbital angular momentum and the use of adaptive optics is discussed. The information capacity per photon is quantified and compared to that using polarization states for binary digits.
We describe an experimental implementation of a free-space 11-dimensional communication system using orbital angular momentum (OAM) modes. This system has a maximum measured OAM channel capacity of 2.12 bits/photon. The effects of Kolmogorov thin-phase turbulence on the OAM channel capacity are quantified. We find that increasing the turbulence leads to a degradation of the channel capacity. We are able to mitigate the effects of turbulence by increasing the spacing between detected OAM modes. This study has implications for high-dimensional quantum key distribution (QKD) systems. We describe the sort of QKD system that could be built using our current technology.
Quantum key distribution (QKD) technology has demonstrated remarkable practicality and sustained developmental trends in the current field of quantum communication. This paper focuses on a novel and potent quantum communication protocol, specifically quantum key distribution utilizing the encoding of information through orbital angular momentum (OAM) of photons. OAM states, owing to their distinctive properties, exhibit significant advantages in terms of information capacity and channel robustness. However, the sensitivity of OAM states to atmospheric conditions and challenges arising from wavefront distortions necessitate in-depth investigation. Additionally, the unique structure of OAM beams has raised concerns about geometric losses. By analyzing the impact of atmospheric turbulence and geometric losses on the transmission performance when applying the OAM-QKD protocol in free space, this paper explores variations in system losses under different OAM orders. Simulation results indicated that as the channel distance increases, system losses gradually escalate. Furthermore, with an increase in OAM order, although the system's sensitivity to atmospheric turbulence diminishes, geometric losses exhibit an exponential increase. Addressing this issue, our research suggested that when considering free-space quantum key distribution with OAM encoding, selecting an OAM order of 1 for the beam achieves minimal transmission losses. Therefore, in practical applications, employing OAM beams with <?TeX l=1l = 1l=1 ?> emerges as an effective strategy to optimize the performance of the OAM-QKD protocol in free space.
We study a quantum few-mode fiber (FMF) communication scheme based on orbital angular momentum (OAM) modes and applied quantum information theory to develop the quantum FMF channel model and to calculate the quantum channel capacity. We assume a strong mode-coupling regime in FMF and an imperfect generation of OAM modes. The quantum FMF channel is modeled as a concatenation of many fiber sections describing the OAM eigenkets transitions as a Markov chain. The proposed model is suitable for the study of the multidimensional quantum key distribution and teleportation over FMFs. Numerical simulations are performed to demonstrate the ability of the model to determine the FMF output density state for a given input density state. It is shown that FMF quantum channel capacity decreases with distance in a strong coupling regime if OAM basekets are imperfectly generated.
In this paper, a free-space quantum key distribution (QKD) system based on BB84 protocol is studied assuming that the transmitted quantum bits are multiplexed spatially based on orthogonal orbital angular momentum (OAM) carrying beams. The performance of such a system is estimated in terms of quantum bit error rate, outage capacity, and effective data rate taking into account the impact of error correction and privacy amplification. Based on the simulation of OAM-carrying beam propagating through atmospheric channels impaired by turbulence, the crosstalk among the multiplexed channels are investigated and its effect on the performance of the QKD system is evaluated. The presented results provide insight into the efficient design of such multiplexed QKD systems particularly in terms of the choice of the optimal average photon number per pulse and the multiplexing mode set.