Photonic chip design offers simpler solution for one-way light flow in optical circuits

https://phys.org/news/2025-05-photonic-chip-simpler-solution-optical.html

"parity-time symmetric photonic waveguides mirror-flips light waves to 'reverse time' so system behaves same as before... tiny pieces of metal along the waveguides serve as light traps, enabling reconfigurable transmission for asymmetric transmission simplifying telecommunication... waveguide control eliminates need for complex/ bulky isolator components... Floquet non-Hermitian physics periodical system, mimicing rotated polarizers effect... reduces cross-talk... semiconductors, fiber optics, lasers, sensors"

Related: A superconducting diode: Researchers successfully control the direction of current in a superconductor
https://phys.org/news/2025-05-superconducting-diode-successfully-current-superconductor.html