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

Chinese Optics Letters

Transforming information from spin encoding to route encoding

Aiping Liu Aiping Liu, Xiao Xiong, Xi‐Feng Ren, Guang-Can Guo

Published Jan 1, 2014• 1 citation
Publisher

Abstract

Spin (polarization) is widely used in free-space optics, while in photonic integrated circuits (PICs), information is usually encoded in optical route.So a practical way to connect these two encoding methods is necessary for information communication.In this letter, an encoding convertor is designed to connect spin encoding and route encoding.Finite element method is used to calculate the conversion efficiency and extinction ratio of the encoding convertor and the theoretical analyses are also given.Our protocol shows a friendly way to convert optical spin information to route information, which will promote the compatibility of free-space optics and PICs.

DOI
10.3788/col201412.072401

Related papers

A polarization encoded photon-to-spin interface

K. C. Chen, Eric A. Bersin, Dirk Englund

Abstract We propose an integrated photonics device for mapping qubits encoded in the polarization of a photon onto the spin state of a solid-state defect coupled to a photonic crystal cavity: a “polarization-encoded photon-to-spin interface” (PEPSI). We perform a theoretical analysis of the state fidelity’s dependence on the device’s polarization extinction ratio and atom–cavity cooperativity. Furthermore, we explore the rate-fidelity trade-off through analytical and numerical models. In simulation, we show that our design enables efficient, high fidelity photon-to-spin mapping.

arXiv:2004.02381•npj Quantum Information•Jan 4, 2021•25 citations

On-chip coherent conversion of photonic quantum entanglement between different degrees of freedom

Lan‐Tian Feng, Ming Zhang, Zhi‐Yuan Zhou +8 more

In the quantum world, a single particle can have various degrees of freedom to encode quantum information. Controlling multiple degrees of freedom simultaneously is necessary to describe a particle fully and, therefore, to use it more efficiently. Here we introduce the transverse waveguide-mode degree of freedom to quantum photonic integrated circuits, and demonstrate the coherent conversion of a photonic quantum state between path, polarization and transverse waveguide-mode degrees of freedom on a single chip. The preservation of quantum coherence in these conversion processes is proven by single-photon and two-photon quantum interference using a fibre beam splitter or on-chip beam splitters. These results provide us with the ability to control and convert multiple degrees of freedom of photons for quantum photonic integrated circuit-based quantum information process.

arXiv:1601.06250•Nature Communications•Jun 20, 2016•138 citations

Towards the on-chip realization of polarization encoded qubits

Duncan L. MacFarlane, Adam Helmy, Hiva Shahoei +4 more

While photonic quantum circuits may be implemented using polarization-encoded qubits, their photonic integrated circuit (PIC) realization has been limited by on-chip impairments such as mode dispersion and polarization state stability that do not hinder bulk-optic, table-top setups. In this paper, we will present an interpretation of on-chip polarization and provide the beginning of a portfolio of components that may be used for polarization-encoded qubits. Central to our work is the use of waveguides of square cross-section, which symmetrically support orthogonal TE and TM modes with perpendicular electric fields. Preliminary designs for components to manipulate these modes are presented, along with measurements relevant to polarization in PICs. The research has relevance, as well, to sensing and security.

SPIE Quantum Information Science, Sensing, and Computation•Jun 7, 2024•1 citation

Integrated optics-based quantum communication devices

Rohit K. Ramakrishnan, Shafeek A. Samad, Kande Archana +3 more

Quantum communication or more specifically quantum information processing is considered as the future of information science and technology. In this paper we propose a scheme to implement quantum communication at the device level using integrated optics. We implement the quantum communication protocol BB84, in a waveguide based circuit using integrated optics. We also propose a high dimensional quantum key distribution method implementation using integrated optics. In the earlier one polarized photons are used as the carriers of quantum information, while in second one electromagnetic modes in the waveguide are used to carry quantum information. The high dimensional quantum communication method is used to increase the information content of protocol thus increasing on the data rates. This is done by encoding into a larger state space. We have used electromagnetic modes for encoding since the polarization method is not efficient to carry information in a larger state space.

Proceedings of SPIE, the International Society for Optical Engineering/Proceedings of SPIE•Feb 20, 2017•1 citation

Atomic-Scale On-Demand Photon Polarization Manipulation with High Efficiency for Integrated Photonic Chips

Yunning Lu, Zeyang Liao, Xuehua Wang

In order to overcome the challenge of lacking polarization encoding in integrated quantum photonic circuits, we propose a scheme to realize arbitrary polarization manipulation of a single photon by integrating a single quantum emitter in a photonic waveguide. In our scheme, one transition path of the three-level emitter is designed to simultaneously couple with two orthogonal polarization degenerate modes in the waveguide with adjustable coupling strengths, and the other transition path of the three-level emitter is driven by an external coherent field. The proposed polarization converter has several advantages, including arbitrary polarization conversion for any input polarization, tunable working frequency, excellent antidissipation ability with high-conversion efficiency, and atomic-scale size. Our Letter provides an effective solution to enable the polarization encoding of photons that can be applied in the integrated quantum photonic circuits, and will boost quantum photonic chips.

arXiv:2409.17947•Physical Review Letters•Feb 27, 2025•15 citations

Implementation of an efficient linear-optical quantum router

Karol Bartkiewicz, Antonín Černoch, Karel Lemr

For several decades, scientists have been aware of significant benefits allowing quantum information processing technologies to surpass their classical counterparts. Recent technological development allows these benefits to be tested experimentally and in some cases also implemented in practical devices. So far the majority of experimental quantum networks was limited to peer-to-peer communications between two parties. Practical implementation of quantum communications networks, however, needs to address the problem of scalability to serve large numbers of users. Similarly to classical computer networks, their quantum counterparts would require routing protocols to direct the signal from its source to destination. Devices implementing these routing protocols are called quantum routers and have recently been subject of an intense research. In this paper, we report on experimental implementation of a linear-optical quantum router. Our device allows single-photon polarization-encoded qubits to be routed coherently into two spatial output modes depending on the state of two identical control qubits. The polarization qubit state of the routed photon is maintained during the routing operation. The success probability of our scheme can be increased up to 25% making it the most efficient linear-optical quantum router developed to this date.

arXiv:1802.05741•Scientific Reports•Sep 3, 2018•17 citations
Spin (polarization) is widely used in free-space optics, while in photonic integrated circuits (PICs), information is usually encoded in optical route.So a practical way to connect these two encoding methods is necessary for information communication.In this letter, an encoding convertor is designed to connect spin encoding and route encoding.Finite element method is used to calculate the conversion efficiency and extinction ratio of the encoding convertor and the theoretical analyses are also given.Our protocol shows a friendly way to convert optical spin information to route information, which will promote the compatibility of free-space optics and PICs.
Abstract We propose an integrated photonics device for mapping qubits encoded in the polarization of a photon onto the spin state of a solid-state defect coupled to a photonic crystal cavity: a “polarization-encoded photon-to-spin interface” (PEPSI). We perform a theoretical analysis of the state fidelity’s dependence on the device’s polarization extinction ratio and atom–cavity cooperativity. Furthermore, we explore the rate-fidelity trade-off through analytical and numerical models. In simulation, we show that our design enables efficient, high fidelity photon-to-spin mapping.
In the quantum world, a single particle can have various degrees of freedom to encode quantum information. Controlling multiple degrees of freedom simultaneously is necessary to describe a particle fully and, therefore, to use it more efficiently. Here we introduce the transverse waveguide-mode degree of freedom to quantum photonic integrated circuits, and demonstrate the coherent conversion of a photonic quantum state between path, polarization and transverse waveguide-mode degrees of freedom on a single chip. The preservation of quantum coherence in these conversion processes is proven by single-photon and two-photon quantum interference using a fibre beam splitter or on-chip beam splitters. These results provide us with the ability to control and convert multiple degrees of freedom of photons for quantum photonic integrated circuit-based quantum information process.
While photonic quantum circuits may be implemented using polarization-encoded qubits, their photonic integrated circuit (PIC) realization has been limited by on-chip impairments such as mode dispersion and polarization state stability that do not hinder bulk-optic, table-top setups. In this paper, we will present an interpretation of on-chip polarization and provide the beginning of a portfolio of components that may be used for polarization-encoded qubits. Central to our work is the use of waveguides of square cross-section, which symmetrically support orthogonal TE and TM modes with perpendicular electric fields. Preliminary designs for components to manipulate these modes are presented, along with measurements relevant to polarization in PICs. The research has relevance, as well, to sensing and security.
Quantum communication or more specifically quantum information processing is considered as the future of information science and technology. In this paper we propose a scheme to implement quantum communication at the device level using integrated optics. We implement the quantum communication protocol BB84, in a waveguide based circuit using integrated optics. We also propose a high dimensional quantum key distribution method implementation using integrated optics. In the earlier one polarized photons are used as the carriers of quantum information, while in second one electromagnetic modes in the waveguide are used to carry quantum information. The high dimensional quantum communication method is used to increase the information content of protocol thus increasing on the data rates. This is done by encoding into a larger state space. We have used electromagnetic modes for encoding since the polarization method is not efficient to carry information in a larger state space.
In order to overcome the challenge of lacking polarization encoding in integrated quantum photonic circuits, we propose a scheme to realize arbitrary polarization manipulation of a single photon by integrating a single quantum emitter in a photonic waveguide. In our scheme, one transition path of the three-level emitter is designed to simultaneously couple with two orthogonal polarization degenerate modes in the waveguide with adjustable coupling strengths, and the other transition path of the three-level emitter is driven by an external coherent field. The proposed polarization converter has several advantages, including arbitrary polarization conversion for any input polarization, tunable working frequency, excellent antidissipation ability with high-conversion efficiency, and atomic-scale size. Our Letter provides an effective solution to enable the polarization encoding of photons that can be applied in the integrated quantum photonic circuits, and will boost quantum photonic chips.
For several decades, scientists have been aware of significant benefits allowing quantum information processing technologies to surpass their classical counterparts. Recent technological development allows these benefits to be tested experimentally and in some cases also implemented in practical devices. So far the majority of experimental quantum networks was limited to peer-to-peer communications between two parties. Practical implementation of quantum communications networks, however, needs to address the problem of scalability to serve large numbers of users. Similarly to classical computer networks, their quantum counterparts would require routing protocols to direct the signal from its source to destination. Devices implementing these routing protocols are called quantum routers and have recently been subject of an intense research. In this paper, we report on experimental implementation of a linear-optical quantum router. Our device allows single-photon polarization-encoded qubits to be routed coherently into two spatial output modes depending on the state of two identical control qubits. The polarization qubit state of the routed photon is maintained during the routing operation. The success probability of our scheme can be increased up to 25% making it the most efficient linear-optical quantum router developed to this date.