Abstract Quantum networks based on atomic qubits and scattered photons provide a promising way to build a large‐scale quantum information processor. We review quantum protocols for generating entanglement and operating gates between two distant atomic qubits, which can be used for constructing scalable atom–photon quantum networks. We emphasize the crucial role of collecting light from atomic qubits for large‐scale networking and describe two techniques to enhance light collection using reflective optics or optical cavities. A brief survey of some applications for scalable and efficient atom–photon networks is also provided.
Abstract Quantum networks based on atomic qubits and scattered photons provide a promising way to build a large‐scale quantum information processor. We review quantum protocols for generating entanglement and operating gates between two distant atomic qubits, which can be used for constructing scalable atom–photon quantum networks. We emphasize the crucial role of collecting light from atomic qubits for large‐scale networking and describe two techniques to enhance light collection using reflective optics or optical cavities. A brief survey of some applications for scalable and efficient atom–photon networks is also provided.
Quantum networks based on atomic qubits and scattered photons provide a promising way to build a largescale quantum information processor. We review quantum protocols for generating entanglement and operating gates between two distant atomic qubits, which can be used for constructing scalable atom–photon quantum networks. We emphasize the crucial role of collecting light from atomic qubits for large-scale networking and describe two techniques to enhance light collection using reflective optics or optical cavities. A brief survey of some applications for scalable and efficient atom–photon networks is also provided. 1
Quantum information science possesses promising potentialities for developing new secure and efficient ways to transfer and process information. Prodigious efforts have been and are being devoted, however, a scalable architecture is still a considerable challenge. Among the potential candidates, photons are assumed to be good carriers, and neutral atoms good hosts. In this thesis, photon-matter entanglement sources, which exploit the advantages of both, are employed to demonstrate a teleportation between two atomic-ensemble quantum memory nodes and an efficient entanglement swapping, which are essential for scalable quantum networks. Later, the entanglement source is further developed, and an active feedforward one-way quantum computation is presented \nwith stationary quantum memories, which are necessary for scalable quantum computers. To fulfill another feature of scalability, the ease of integration, ultracold atoms in \ntwo-dimensional optical superlattices are studied and an experiment is designed to generate four-qubit entangled states. With the help of the photon-matter entanglement \nsources, serving as quantum memories and nodes of quantum networks, realization of large-scale quantum networks is foreseeable. Meanwhile, by applying controllable interactions, large entangled states could be generated in optical superlattices, which might help to construct quantum processors that outperform the classical counterparts.
We propose a simple interaction protocol to be implemented on a scalable quantum network, in which the quantum nodes consist of qubit systems confined in cavities. The nodes are deterministically coupled by transmission and reflection of a single photon, which is disentangled from the qubits at the end of the coupling operation. This single photon can generate an entangling controlled-phase gate between any selected number of qubits in the network. Our multiqubit gate reaches a much higher fidelity compared to schemes concatenating one-qubit and two-qubit gates; thus it forms an efficient basis for universal quantum computing distributed over multiple processor units. In our analysis we consider atomic qubits coupled to optical photons, while the scheme can be readily generalized to other architectures, such as superconducting qubit nodes coupled by microwave photons.
ABSTRACT The rapid growth of global data traffic and the increasing demand for secure and scalable communication are driving the need for networking paradigms beyond the classical internet. The quantum internet has emerged as a promising solution, leveraging the principles of quantum mechanics to enable intrinsically secure communication, and computation. In this paper, we present a comprehensive review of the fundamental building blocks and system architectures required for large‐scale quantum networks, with a particular focus on photonic hardware platforms. We introduce key concepts of quantum information relevant to networking, including qubits, entanglement, and decoherence, and examine enabling technologies across different qubit platforms, highlighting photonic qubits as the primary carriers for long‐distance communication. We review major deterministic and probabilistic entanglement generation techniques, and analyze entanglement distribution strategies based on fiber, satellite, and quantum repeater architectures. Beyond the physical layer, we provide a system‐level perspective on quantum networking through protocol stack design, as well as challenges in entanglement routing, forwarding, and scheduling. Finally, we discuss experimental testbeds for entanglement distribution in both fiber‐based and free‐space systems, and outline the corresponding challenges and future research directions, including satellite‐assisted architectures for achieving scalable and globally connected quantum networks.
Distributing entanglement between distant qubits is a crucial element of scalable quantum computing. Here, we describe a scalable quantum interconnect that generates remote entanglement at rates approaching those compatible with two-qubit gates of current neutral-atom quantum processors. The proposed approach exploits the strong dipole-dipole interactions between atomic Rydberg states to generate entanglement between stationary qubits and propagating photons, without the need for an optical cavity. We provide a thorough description of the optimal conditions for the developed entanglement-generation protocol for realistic experimental parameters and demonstrate that entanglement-generation rates ≳3×105 s−1 can be achieved using Rydberg states of ytterbium atoms. Given the inherent scalability and design flexibility of the proposed interconnect, our results suggest a promising approach towards distributed networks based on neutral-atom quantum architectures.
Abstract Quantum network is constituted by quantum channels and quantum nodes. The interaction between non‐classical optical modes and quantum nodes, as well as quantum entanglement among multiple distant quantum nodes are the building blocks of quantum network, which enable to achieve a plethora of quantum information protocols, such as distributed quantum computation, quantum state transfer across quantum nodes, and quantum clock network. On one hand, the multipartite non‐classical states of optical modes, which can directly interact with atomic ensembles, are required for the practical applications of quantum network. On the other hand, a crucial goal of quantum network is to unconditionally generate and on‐demand store and retrieve multipartite entangled states in atomic ensembles. This paper presents an up‐to‐date review on recent developments in these areas: multipartite continuous‐variable polarization entangled optical modes have been created by transforming quantum state from quadrature into polarization components; and a scalable quantum network with deterministic entanglement among multiple quantum memories has been constructed by transferring spatially separated entangled optical modes into atomic ensembles.