Thin 2D tungsten diselenide rotates light polarisation

https://www.uni-muenster.de/news/view.php?cmdid=13997&lang=en

"...of visible light by several degrees at certain wavelengths under small magnetic fields... miniaturised optical isolators for on-chip integration of optical computer technologies... also, bulky magnets, which are also required for optical isolators, could be made 2-D magnets, reducing size of photonic ICs... bound electron-hole pairs (excitons) in 2D semiconductors rotate light polarisation when the 2D material is placed in small magnetic field"