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arXiv · 2211.16343

Quantum Repeater using Two-Mode Squeezed States and Atomic Noiseless Amplifiers

Anders J. E. Bjerrum·Jonatan B. Brask·Jonas S. Neergaard-Nielsen·Ulrik L. Andersen
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Abstract

We perform a theoretical investigation into how a two-mode squeezed vacuum state, that has undergone photon loss, can be stored and purified using noiseless amplification with a collection of solid-state qubits. The proposed method may be used to probabilistically increase the entanglement between the two parties sharing the state. The proposed amplification step is similar in structure to a set of quantum scissors. However, in this work the amplification step is realized by a state transfer from an optical mode to a set of solid-state qubits, which act as a quantum memory. We explore two different applications, the generation of entangled many-qubit registers, and the construction of quantum repeaters for long-distance quantum key distribution.

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Anders J. E. Bjerrum, Jonatan B. Brask, Jonas S. Neergaard-Nielsen, Ulrik L. Andersen. 2022-11-28. Quantum Repeater using Two-Mode Squeezed States and Atomic Noiseless Amplifiers. https://doi.org/10.1103/physreva.107.042606

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