Quantum repeater based on cavity-QED evolutions and coherent light
arXiv:1609.04067 · doi:10.1007/s00340-016-6388-x
Abstract
In the framework of cavity QED, we propose a quantum repeater scheme that uses coherent light and chains of atoms coupled to optical cavities. In contrast to conventional repeater schemes, we avoid the usage of two-qubit quantum logical gates by exploiting solely the cavity QED evolution. In our previous paper [D. Gonta and P. van Loock: Phys. Rev. A 88, 052308 (2013)], we already proposed a quantum repeater in which the entanglement between two neighboring repeater nodes was distributed using controlled displacements of input coherent light, while the produced low-fidelity entangled pairs were purified using ancillary (four-partite) entangled states. In this paper, the entanglement distribution is realized using a sequence of controlled phase shifts and displacements of input coherent light. Compared to previous coherent-state-based distribution schemes for two-qubit entanglement, the present scheme relies only upon a simple discrimination of two coherent states with opposite signs, which can be performed in a quantum mechanically optimal fashion via a beam splitter and two on-off detectors. The entanglement purification utilizes a scheme that avoids the usage of ancillary entangled resources. Our repeater scheme exhibits reasonable fidelities and repeater rates providing an attractive platform for long-distance quantum communication.
22 pages, 5 figures. version accepted in Applied Physics B (topical collection: Quantum Repeaters - From Components to Strategies). arXiv admin note: text overlap with arXiv:1309.1668
References in corpus (13)
- Quantum repeaters based on entanglement purification
- Quantum teleportation and entanglement distribution over 100-kilometre free-space channels
- Hybrid quantum repeater using bright coherent light
- Ultrafast and Fault-Tolerant Quantum Communication across Long Distances
- Cooling to the Ground State of Axial Motion for One Atom Strongly Coupled to an Optical Cavity
- Coherence properties and quantum state transportation in an optical conveyor belt
- A Hybrid Long-Distance Entanglement Distribution Protocol
- Distribution of entanglement in large-scale quantum networks
- Rate analysis for a hybrid quantum repeater
- A high bandwidth quantum repeater
- Quantum jumps and spin dynamics of interacting atoms in a strongly coupled atom-cavity system
- Photon-assisted entanglement creation by minimum-error generalized quantum measurements in the strong coupling regime
- Dynamical quantum repeater using cavity-QED and optical coherent states