During the '90s, engineers made major advances in the telecom arena spreading out the network to distances beyond the cities and metropolitan areas. To achieve this scalability factor, they used repeaters, which enhanced attenuated signals and allowed these to travel farther distances with the same features such as intensity or fidelity. Now, with the addition of satellites, it is completely normal to be in the middle of a mountain in Europe and talk with your loved ones living in the other part of the world.
In the road towards building the future quantum internet, quantum memories play the same role. Together with sources of qubits, they are the building blocks of this novel internet, acting as quantum repeaters of data operations and using superposition and entanglement as the key ingredients of the system. But to operate such system at a quantum level, the entanglement between quantum memories had to be created over long distances and maintained as efficiently as possible.
In a recently published study in Nature, ICFO scientists Dario Lago, Samuele Grandi, Alessandro Seri and Jelena Rakonjac, led by ICREA Prof at ICFO, Hugues de Riedmatten, have achieved scalable, telecom-heralded matter-matter entanglement between two remote, multimode and solid-state quantum memories. In simpler words, they were able to store, for a maximum of 25 microseconds, one single photon in two quantum memories placed 10 meters apart.
To read more, click here.