Routing signals and isolating them against noise and back-re­flections are essential in many practical situations in classical communication as well as in quantum information processing. In a the­ory-experimental collaboration, an international research team has achie­ved unidirectional transport of signals in pairs of “one-way streets”: Different signal components are transmitted in opposite direction while the transmission in the reverse direction is fully suppressed. This research – led by Andreas Nunnenkamp from the University of Vienna and AMOLF group leader Ewold Ver­hagen and involving the Max Planck Institute for the Science of Light – was published in Nature Physics and opens up new possibilities for more flexible signalling devices.

The research team: Clara Wanjura (MPL), Jesse Slim (AMOLF), Javier del Pino (ETH), Matteo Brunelli (Basel), Ewold Verhagen (AMOLF) and Andreas Nunnenkamp (University of Vienna).

Publication: C.C. Wanjura, J.J. Slim, J. del Pino, M. Brunelli, E. Verhagen, A. Nunnenkamp. Quadrature nonreciprocity in bosonic networks without breaking time-reversal symmetry. Nat. Phys. (2023).

You can read our full press release here: https://mpl.mpg.de/fileadmin/user_upload/Pressemitteilungen/PM_to_lane_highway_for_signals_2023_eng.pdf

And you can find the publication here:
https://www.nature.com/articles/s41567-023-02128-x 

Image 1 (@ EddieCloud/Shutterstock.com modified by C. C. Wanjura): A dual carriageway for signals. One quadrature is transmitted in one direction, the other quadrature in the other direction.

Image 2 (@ C. C. Wanjura): Illustration of the nanomechanical system whose vibrations are coupled by light.