Quantum communication in a higher dimensional system provides a higher capacity, more secure, and smaller latency compared to that of quantum communications based on 2-dimensional system or qubit. This paper studies a simple design of quantum communications based on orbital angular momentum (OAM). We consider two system models for quantum communications based on OAM, i.e., (i) a general structure of a simple OAM-based quantum communication system and (ii) a simple quantum error correction coding scheme for 3-dimensional system or quantum ternary digit (qutrit). We theoretically evaluate the possible construction of OAM-based quantum communications supported by qutrit-based error corrections. We found that OAM-based quantum communications are possibly supported by the derived controlled-NOT (CNOT) gate and stabilizers for qutrit bit flip error corrections. The qutrit stabilizers have shown that they can completely correct all qutrit single bit-flip errors. The results are expected to open new development on qudit-based quantum communications and error corrections.
Quantum communication in a higher dimensional system provides a higher capacity, more secure, and smaller latency compared to that of quantum communications based on 2-dimensional system or qubit. This paper studies a simple design of quantum communications based on orbital angular momentum (OAM). We consider two system models for quantum communications based on OAM, i.e., (i) a general structure of a simple OAM-based quantum communication system and (ii) a simple quantum error correction coding scheme for 3-dimensional system or quantum ternary digit (qutrit). We theoretically evaluate the possible construction of OAM-based quantum communications supported by qutrit-based error corrections. We found that OAM-based quantum communications are possibly supported by the derived controlled-NOT (CNOT) gate and stabilizers for qutrit bit flip error corrections. The qutrit stabilizers have shown that they can completely correct all qutrit single bit-flip errors. The results are expected to open new development on qudit-based quantum communications and error corrections.
Orbital angular momentum (OAM) of photons provides a promising approach to enhance the capacity, robustness, and functionality of quantum communication systems in optical fibers. With many twist states available, OAM enables high-dimensional encoding, significantly increasing data rates and noise tolerance. This review explores sources, channels, and system architectures for OAM-based quantum communication in fibers. It compares free-space and integrated emitters, discussing in-fiber pair generation and mode conversion pathways that produce fiber-ready single photons and entangled states. For the channels, it details design principles and trade-offs for step-index and ring-core fibers that minimize intermodal coupling and reviews milestones in kilometer-scale single-photon transmission and high-dimensional entanglement transport. On the system side, the review examines coupling, multiplexing, and detection techniques—including mode (de)multiplexers, lanterns, and programmable sorters—and discusses transmission-matrix-based control methods to mitigate dispersion and bending effects. The review concludes with practical guidance and open challenges, such as improving mode selectivity and stability under real-world conditions; developing compact, efficient detectors for many modes; and integrating co-designed error correction schemes. These directions aim to bridge laboratory demonstrations with the deployment of scalable, high-dimensional fiber networks that harness OAM to significantly boost capacity, resilience, and functionality.
Satellite-based quantum communications enable a bright future for global-scale information security. However, the spin angular momentum of light, currently used in many mainstream quantum communication systems, only allows for quantum encoding in a two-dimensional Hilbert space. The orbital angular momentum (OAM) of light, on the other hand, enables quantum encoding in higher-dimensional Hilbert spaces, opening up new opportunities for high-capacity quantum communications. Due to its turbulence-induced decoherence effects, however, the atmospheric channel may limit the practical usage of OAM. In order to determine whether OAM is useful for satellite-based quantum communications, we numerically investigate the detection likelihoods for OAM states that traverse satellite-to-ground channels. We show that the use of OAM through such channels is in fact feasible. We use our new results to then investigate design specifications that could improve OAM detection - particularly the use of advanced adaptive optics techniques. Finally, we discuss how our work provides new insights into future implementations of space-based OAM systems within the context of quantum communications.
The existing quantum secure direct communication (QSDC) protocols mainly make use of the spin angular momentum and entangled photons, to realize direct transmission of confidential information. But those protocols' capacity is low, only one-bit information. On the other hand, the orbital angular momentum (OAM) of a photon can be theoretically evaluated from minus infinity to infinity, and the angular momentum states of different orbits are orthogonal to each other. Given that, in this paper, we propose a quantum secure direct communication scheme based on OAM. Specifically, taking OAM of photons as the information carrier, the data of information is segmented and high-capacity coding in quantum secure direct communication is realized through the segmentation of sector states.
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.
Higher channel capacity and noise elimination are the key requirements for the implementation of long-distance quantum communication. As the additional degrees of freedom (DoF) of photons can be employed to achieve higher channel capacity and security beyond the polarizations DoF of photons, the photonic qubits are always employed as the flying qubits in quantum communication and quantum information processing. Here, exploiting the multiple DoFs of photons, we present an efficient quantum secure direct communication protocol based on the coding and manipulation of qubits on both the polarization and the orbital angular momentum of photons. Also, the numerical simulation is studied to further clarify the improvement of the channel capacity and the security. It is found that the channel capacity and the error rate (caused by eavesdropping) of the QSDC protocol which encoded on the polarization DoF and the OAM DoF is significantly higher than that of coding on only polarization DoF. We believe this work could provide more evidence for the applications of higher-dimensional qubits in quantum information science.
Recently,the free space optical communication system based on orbital angular momentum( OAM) states multiplexing has become one of the hot topics in optical communications and quantum optics,because OAM states are new dimensional information carriers. An efficient orbital-angular-momentum-multiplexed free-space optical communication scheme is proposed,where the efficient orbital angular momentum states separation method is adopted. With this OAM separation method,different orbital angular momentum states can be obtained simultaneously from the superposition OAM state beam,which greatly saves time and the expensive devices for demodulating the information from the information-carrying OAM states. Numerical simulation results show that the proposed scheme can reduce time and the number of the devices at the receiver for the information retrieving. The bit error rate of the system can be less than 10- 4when the signal-to-noise ratio of the system is greater than 23 dB. Therefore,this OAMmultiplexed free-space optical communications scheme is proved to be feasible.