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

arXiv:2011.03250 · National Science Open

Programmable unitary operations for orbital angular momentum encoded states

Shikang Li, Xue Feng, Kaiyu Cui, Fang Liu, Wei Zhang, Yidong Huang

Published Jan 1, 2022• 9 citations
arXivHTMLPDF

Abstract

We have proposed and demonstrated a scalable and efficient scheme for programmable unitary operations in orbital angular momentum (OAM) domain. Based on matrix decomposition into diagonal and Fourier factors, arbitrary matrix operators can be implemented only by diagonal matrices alternately acting on orbital angular momentum domain and azimuthal angle domain, which are linked by Fourier transform. With numerical simulations, unitary matrices with dimensionality of 3×3 are designed and discussed for OAM domain. Meanwhile, the parallelism of our proposed scheme is also presented with two 3×3 matrices. Furthermore, as an alternative to verify our proposal, proof of principle experiments have been performed on path domain with the same matrix decomposition method, in which an average fidelity of 0.97 is evaluated through 80 experimental results with dimensionality of 3×3.

DOI
10.1360/nso/20220019

Related papers

Implementing Unitary Operators with Decomposition into Diagonal Matrices of Transform Domains

Shikang Li, Xue Feng, Kaiyu Cui +3 more

We have proposed and demonstrated a general and scalable scheme for programmable unitary gates. Our method is based on matrix decomposition into diagonal and Fourier factors. Thus, we are able to construct arbitrary matrix operators only by diagonal matrices alternately acting on two photonic encoding bases that belong to a Fourier transform pair. Thus, the technical difficulties to implement arbitrary unitary operators are significantly reduced. As examples, two protocols for optical OAM and path domain are considered to verify our proposal and evaluate the performance. For OAM domain, unitary matrices with dimensionality up to 6*6 are achieved and discussed with the numerical simulations. For path domain, an average fidelity of 0.98 is evaluated through 80 experimental results with dimensionality of 3*3. Furthermore, our proposal is also potential to provide a quantum operation protocol for any other photonic domain, if there exists the corresponding transformed domain.

•Nov 6, 2020•5 citations

Fourier Transform of the Orbital Angular Momentum of a Single Photon

Jaroslav Kysela, Xiaoqin Gao, Borivoje Dakić

Optical networks implementing single-qudit quantum gates may exhibit superior properties to those for qubits as each optical element in the network can work in parallel on many optical modes simultaneously. We present a class of such networks that implements in a deterministic and efficient way the quantum Fourier transform (QFT) in an arbitrarily high dimension. These networks redistribute the initial quantum state into the orbital angular momentum (OAM) and path degrees of freedom and offer two modes of operation. Either the OAM-only QFT can be implemented, which uses the path as an internal auxiliary degree of freedom, or the path-only QFT is implemented, which uses the OAM as the auxiliary degree of freedom. The resources for both schemes scale linearly $O(d)$ with the dimension $d$ of the system, beating the best known bounds for the path-encoded QFT. While the QFT of the orbital-angular-momentum states of single photons has been applied in a multitude of experiments, these schemes require specially designed elements with nontrivial phase profiles. In contrast, we propose a different approach that utilizes only conventional optical elements.

arXiv:2004.12788•Physical Review Applied•Sep 14, 2020•15 citations

Arbitrary unitaries in orbital angular momentum of single photons

Jaroslav Kysela

Abstract A simple argument is presented that explicitly shows how to construct an arbitrary quantum gate acting on orbital angular momentum (OAM) of single photons. The scheme can be applied to implement subspace multiplexing, where a single high-dimensional OAM qudit represents effectively a stack of multiple independent lower-dimensional qudits. A special subclass of unitaries composed of single-photon controlled gates is studied in detail and notable examples of the general approach are discussed. The generalization of the simple argument leads to the parallelization scheme, which results in the savings of resources. The presented schemes utilize only conventional optical elements and apply not only to single photons but also to classical light.

arXiv:2106.11046•EPJ Quantum Technology•Aug 17, 2022•1 citation

Integrated High-dimensional Orbital Angular Momentum Entangled Photon Source

Jieshan Huang, Xudong Li, Jingze Yuan +3 more

We experimentally demonstrate the generation of arbitrary entangled 2-photon 5-dimensional orbit angular momentum(OAM) states on a programmable silicon photonic chip. High-dimensional witness and tomography are used to verify the genuine entanglement.

•Jan 1, 2024•0 citations

Orbital angular momentum of light towards implementation of high-dimensional quantum gates

Juan Carlos Rojas Velásquez

High-dimensional quantum computing has emerged as a recent alternative to conventional qubit-based approaches, offering advantages such as an increased information density and enhanced robustness against noise. In this work, we explore the use of the orbital angular momentum (OAM) of light as a degree of freedom in which high-dimensional quantum gates can be implemented. We present a theoretical and experimental study of structured light beams carrying OAM, with emphasis on Laguerre–Gauss modes, as a natural basis for high-dimensional quantum computing. We then describe the generation of OAM beams using computer-generated holograms and spatial light modulators, detailing practical methods for encoding arbitrary phase profiles. Building on this framework, we analyze the implementation of high-dimensional quantum logic gates, focusing on the generalized Pauli Z_d and X_d operations. Optical setups based on Dove prisms, Sagnac interferometers, spiral phase plates, and parity sorters are proposed and theoretically validated. Finally, we report experimental results demonstrating the generation of Laguerre–Gauss beams, the transformation properties of Dove prisms, and the operation of a parity sorter, which constitutes a building block for realizing high-dimensional quantum gates. These results establish a solid foundation for future implementations of high-dimensional quantum information processing using the orbital angular momentum of light.

•Jan 21, 2026•0 citations

Efficient full state tomography of the orbital angular momentum states of light using Helicity sorter

Joel M. Sunil, Goyal, Sandeep K.

Orbital angular momentum (OAM) of light is a promising degree of freedom for quantum communication and quantum computation. However, efficient methods to transform and measure OAM modes are still not available readily. Here, we propose a method for full quantum state tomography for arbitrary OAM states of light. The key component in our scheme is the helicity sorter, a device that can sort OAM modes of a light beam based on their Helicity. We present two setups to implement the Helicity sorted, one requires $\mathcal{O}(N)$ number of optical elements for $2^N$ OAM modes, and the other uses spatial light modulators and is independent of the number of OAM modes. Ours is the first method to provide the efficient and scalable full quantum state tomography of the OAM modes and can be extremely important for quantum communication and quantum computation.

arXiv:2112.06277•Dec 12, 2021•0 citations
We have proposed and demonstrated a scalable and efficient scheme for programmable unitary operations in orbital angular momentum (OAM) domain. Based on matrix decomposition into diagonal and Fourier factors, arbitrary matrix operators can be implemented only by diagonal matrices alternately acting on orbital angular momentum domain and azimuthal angle domain, which are linked by Fourier transform. With numerical simulations, unitary matrices with dimensionality of 3×3 are designed and discussed for OAM domain. Meanwhile, the parallelism of our proposed scheme is also presented with two 3×3 matrices. Furthermore, as an alternative to verify our proposal, proof of principle experiments have been performed on path domain with the same matrix decomposition method, in which an average fidelity of 0.97 is evaluated through 80 experimental results with dimensionality of 3×3.
We have proposed and demonstrated a general and scalable scheme for programmable unitary gates. Our method is based on matrix decomposition into diagonal and Fourier factors. Thus, we are able to construct arbitrary matrix operators only by diagonal matrices alternately acting on two photonic encoding bases that belong to a Fourier transform pair. Thus, the technical difficulties to implement arbitrary unitary operators are significantly reduced. As examples, two protocols for optical OAM and path domain are considered to verify our proposal and evaluate the performance. For OAM domain, unitary matrices with dimensionality up to 6*6 are achieved and discussed with the numerical simulations. For path domain, an average fidelity of 0.98 is evaluated through 80 experimental results with dimensionality of 3*3. Furthermore, our proposal is also potential to provide a quantum operation protocol for any other photonic domain, if there exists the corresponding transformed domain.
Optical networks implementing single-qudit quantum gates may exhibit superior properties to those for qubits as each optical element in the network can work in parallel on many optical modes simultaneously. We present a class of such networks that implements in a deterministic and efficient way the quantum Fourier transform (QFT) in an arbitrarily high dimension. These networks redistribute the initial quantum state into the orbital angular momentum (OAM) and path degrees of freedom and offer two modes of operation. Either the OAM-only QFT can be implemented, which uses the path as an internal auxiliary degree of freedom, or the path-only QFT is implemented, which uses the OAM as the auxiliary degree of freedom. The resources for both schemes scale linearly O(d)O(d)O(d) with the dimension ddd of the system, beating the best known bounds for the path-encoded QFT. While the QFT of the orbital-angular-momentum states of single photons has been applied in a multitude of experiments, these schemes require specially designed elements with nontrivial phase profiles. In contrast, we propose a different approach that utilizes only conventional optical elements.
Abstract A simple argument is presented that explicitly shows how to construct an arbitrary quantum gate acting on orbital angular momentum (OAM) of single photons. The scheme can be applied to implement subspace multiplexing, where a single high-dimensional OAM qudit represents effectively a stack of multiple independent lower-dimensional qudits. A special subclass of unitaries composed of single-photon controlled gates is studied in detail and notable examples of the general approach are discussed. The generalization of the simple argument leads to the parallelization scheme, which results in the savings of resources. The presented schemes utilize only conventional optical elements and apply not only to single photons but also to classical light.
High-dimensional quantum computing has emerged as a recent alternative to conventional qubit-based approaches, offering advantages such as an increased information density and enhanced robustness against noise. In this work, we explore the use of the orbital angular momentum (OAM) of light as a degree of freedom in which high-dimensional quantum gates can be implemented. We present a theoretical and experimental study of structured light beams carrying OAM, with emphasis on Laguerre–Gauss modes, as a natural basis for high-dimensional quantum computing. We then describe the generation of OAM beams using computer-generated holograms and spatial light modulators, detailing practical methods for encoding arbitrary phase profiles. Building on this framework, we analyze the implementation of high-dimensional quantum logic gates, focusing on the generalized Pauli Z_d and X_d operations. Optical setups based on Dove prisms, Sagnac interferometers, spiral phase plates, and parity sorters are proposed and theoretically validated. Finally, we report experimental results demonstrating the generation of Laguerre–Gauss beams, the transformation properties of Dove prisms, and the operation of a parity sorter, which constitutes a building block for realizing high-dimensional quantum gates. These results establish a solid foundation for future implementations of high-dimensional quantum information processing using the orbital angular momentum of light.
Orbital angular momentum (OAM) of light is a promising degree of freedom for quantum communication and quantum computation. However, efficient methods to transform and measure OAM modes are still not available readily. Here, we propose a method for full quantum state tomography for arbitrary OAM states of light. The key component in our scheme is the helicity sorter, a device that can sort OAM modes of a light beam based on their Helicity. We present two setups to implement the Helicity sorted, one requires O(N)\mathcal{O}(N)O(N) number of optical elements for 2N2^N2N OAM modes, and the other uses spatial light modulators and is independent of the number of OAM modes. Ours is the first method to provide the efficient and scalable full quantum state tomography of the OAM modes and can be extremely important for quantum communication and quantum computation.