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One fundamental goal of quantum networks is to provide node-to-node entanglement distribution. In this work, we develop a simulator, called A 2 Tango, for entanglement generation between two remote atom-ensemble nodes in a quantum network following Briegel, Dur, Cirac and Zoller (BDCZ) protocol. We encode quantum information to the two spatial modes of local atomic-ensemble spin waves and polarization states of single photons. The basic operations include atom-photon entanglement generation, quantum memory write-read operations, two-photon Bell-state measurement, and quantum state tomography. We model multi-photon events during the local excitation and propagation to account for their induced error in entanglement generation and distribution. We investigate the entanglement generation rate and fidelity as functions of the parameters which are realizable in experiments. Our work improves the open-sourced SeQUeNCe simulator and inspires the development of future quantum networks.
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Zero-Added-Loss Entangled-Photon Multiplexing for Ground- and Space-Based Quantum Networks
We propose a scheme for optical entanglement distribution in quantum networks based on a quasideterministic entangled photon-pair source. By combining heralded photonic Bell-pair generation with spectral mode conversion to interface with quantum memories, the scheme eliminates switching losses due to multiplexing in the source. We analyze this “zero-added-loss multiplexing” (ZALM) Bell-pair source for the particularly challenging problem of long-baseline entanglement distribution via satellites and ground-based memories, where it unlocks additional advantages: (i) the substantially higher channel efficiency η of downlinks versus uplinks with realistic adaptive optics, and (ii) photon loss occurring before interaction with the quantum memory—i.e., Alice and Bob receiving rather than transmitting—improve entanglement generation rate scaling by O(√η). Based on numerical analyses, we estimate our protocol to achieve >10ebit/s at memory multiplexing of 102 spin qubits for ground distance >102km, with the spin-spin Bell-state fidelity exceeding 99%. Our architecture presents a blueprint for realizing global-scale quantum networks in the near term.
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- Award ID(s):
- 1839155
- PAR ID:
- 10481382
- Publisher / Repository:
- Physical Review Applied
- Date Published:
- Journal Name:
- Physical Review Applied
- Volume:
- 19
- Issue:
- 5
- ISSN:
- 2331-7019
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript
- Journal Article:
- https://doi.org/10.1103/PhysRevApplied.19.054029
