Telecom-heralded entanglement distribution between remote, multimode, solid-state quantum memories

Distribution of quantum information through long distances is a basic need in the field of quantum communications. Quantum teleportation is a protocol that uses quantum entanglement as a resource to transmit quantum information between remote parties. The challenge is therefore reduced to distribute entanglement between distant parties. One solution to this problem is to use quantum repeaters, which combine quantum memories and entanglement swapping, and are the cornerstone of a fibre-based long distance entanglement distribution infrastructure.

 

In the talk I will present our approach towards the realization of quantum repeaters using solid-state quantum memories and non-degenerate photon pair sources. I will first introduce our latest results on long distance teleportation of quantum information from a photonic qubit at telecom wavelength onto a matter qubit stored in a solid-state quantum memory. Then, motivated by the need of further extending the teleportation distance, I will introduce our demonstration of heralded entanglement between remote solid-state quantum memories, a stepping-stone towards a quantum repeater [1].

 

Our approach combines a source that generates entangled photon pairs and a solid-state quantum memory based on praseodymium doped solids. One of the photons is at telecom wavelength in order to minimize the losses through long optical fibres. The other photon is compatible with our quantum memory.

The whole scheme is compatible with a multiplexed operation, a highly desirable feature that allows a great speed-up in entanglement distribution rates [2].

 

1. [1] D. Lago-Rivera, et. al., “Telecom-heralded entanglement between multimode solid-state quantum memories”, Nature, 594, 37-40 (2021)
   
   [2] C. Simon, et. al., “Quantum Repeaters with Photon Pair Source and Multimode Memories”, PRL 98, 190503 (2007)