Discovery of the one-way superconductor, thought to be impossible

https://phys.org/news/2022-04-discovery-one-way-superconductor-thought-impossible.html

"to be sure superconducting diode effect, tried switching the diode; applied same magnitude current in both forward and reverse directions and measured no resistance (superconductivity) in one direction and real resistance (normal conductivity) in other direction... measured while applying magnetic fields of different magnitudes and showed effect was present at 0 applied field and gets killed by applied field... magnetic fields at nanometer scale difficult to control and limit"