Distribution of Multiplexed Continuous‐Variable Entanglement for Quantum Networks

Abstract

Quantum networks, the backbone of the future quantum internet, require flexible and precise control to faithfully share entanglement with different users. These networks will allow multiple applications including distributed quantum computation and information theoretic secure communication. In this scenario, orbital angular momentum (OAM) can be employed to enhance the capacity of quantum information processing and to distribute quantum entanglement in an efficient and scalable way with multiple users. Here, a method for realizing a multiplexed continuous variable (CV) quantum entanglement distribution based on a four‐wave mixing process combined with an active routing technique is experimentally demonstrated. By exploiting Sagnac‐based OAM sorters, the OAM entanglement can be distributed and measured with the different users in a quasi‐complete star network configuration. The generations of multiple sets of OAM multiplexed bipartite CV entanglement with four users and six users are proposed and demonstrated here. In addition, the propagation of one mode through a 1 km of single‐mode fiber shows the applicability of this approach. These results propose and demonstrate a new method for distributing CV entanglement in a quantum network enlarging the range of applicability of CV quantum information protocols.

Non‐Hermitian Control of Multimode Duan‐PPT Criteria and Steering in Energy‐Level Cascaded Four‐Wave Mixing Processes

“…Therefore, employing spontaneous parametric down-conversion (SPDC) is of great importance in generating entangled light beams. [27][28][29][30][31][32][33][34] The application in microwave photonics based on the PT symmetry breaking has also been researched. [35] In this paper, non-Hermitian (EP) control of the energy level dressing system through dephase-rate is similar to the microcavity/waveguide coupling system through loss /gain.…”

“…Therefore, employing spontaneous parametric down‐conversion (SPDC) is of great importance in generating entangled light beams. [ 27–34 ] The application in microwave photonics based on the PT symmetry breaking has also been researched. [ 35 ]…”

Simulation of Grover Search with Polar CH3CN Molecules by Optimal Control Fields

“…[1][2][3] Many physical systems have been used to encode qubits for QC, such as trapped ions, [4,5] neutral atoms, [6,7] quantum dots, [8] nuclear magnetic resonance, [9,10] superconducting circuit, [11][12][13] and optical systems. [14][15][16] They all have their own advantages in DOI: 10.1002/qute.202200129 quantum information processing and can be the possible physical carriers for creating the universal quantum computer. Polar molecules have the long coherence times of neutral atoms [17,18] and can be coupled via the strong long-range electric dipole-dipole interaction, [19,20] which are also recognized as the viable candidates for scalable QC.…”

Entanglement of Six Orbital Angular Momentum Modes with Reconfigurable Topological Charges

“…[1][2][3][4][5][6][7][8][9][10][11][12][13][14][15][16][17] By utilizing entanglement, various quantum information protocols have been implemented, such as quantum teleportation network, [4] controlled quantum dense coding, [2] quantum secret sharing, [18] quantum entanglement swapping, [19] quantum error correction, [20] and quantum network. [21][22][23][24][25] In addition to increasing the scale of entanglement, the flexible adjustment of entanglement, including the properties of the entangled modes, DOI: 10.1002/lpor.202201005 is also of great significance for constructing a reconfigurable quantum network, in which tasks often change as needed.…”