A key technical requirement of any future quantum network is the ability to distribute quantum-entangled resources between two spatially separated points at a high rate and high fidelity. Entanglement distribution protocols based on satellite platforms, which transmit and receive quantum resources directly via free-space optical propagation, are therefore excellent candidates for quantum networking, since the geometry and loss characteristics of satellite networks feasibly allow for up to continental-scale ($\approx {10}^3\mathrm{km}$) over-the-horizon communication without the infrastructure, cost, or losses associated with equivalent fiber-optic networks. In this work, we explore two network topologies commonly associated with quantum networks—entanglement distribution between two satellites in low-Earth orbit mediated by a third satellite and entanglement distribution between two ground stations mediated by a satellite in low-Earth orbit—and two entanglement distribution schemes—one where the central satellite is used as a relay, and the other where the central satellite is used to generate and distribute the entangled resource directly. We compute a bound on the rate of distribution of distillable entanglement achieved by each protocol in each network topology as a function of the network channels for both single-rail discrete-variable (DV) and continuous-variable (CV) resources and use or nonuse of probabilistic quantum noiseless linear amplifiers (NLAs). In the case of atmospheric channels we take into account the turbulent and optical properties of the free-space propagation. We determine that for the triple-satellite network configuration, the optimal strategy is to perform a distributed NLA scheme in either CV or DV, and for the ground-satellite-ground network the optimal strategy is to distribute a DV resource via the central satellite.

Close

PrevNext

View figure in article

• Quantum communication
• Quantum information theory
• Quantum networks
• Quantum repeaters