(SpectrumIEEE) A team of German researchers at Ludwig Maximilian University of Munich has stretched the distance quantum information can travel from stationary quantum memory to optical telecom pulse. The group’s new experiment transfers the information contained in a single quantum bit from an atomic state to a single photon, then sends it through some 20 kilometers of fiber optic cable.
This finding begins to extend the distance over which quantum systems (including quantum computers and quantum communications hubs) can be physically separated while still remaining connected. “One of the grand goals is a quantum network, which then would link together different quantum computers,” says Harald Weinfurter, professor of physics at Ludwig Maximilian University of Munich, Germany. “And if we can establish entanglement between many such segments, then we can link all the segments together. And then link, in an efficient manner, two atoms over a really long distance.”