Material found in smartphone screens can be harnessed to map magnetic fields

https://newsroom.unsw.edu.au/news/science-tech/material-found-smartphone-screens-can-be-harnessed-map-magnetic-fields?utm_source=reddit&utm_medium=social

"smartphones portable quantum sensors ... magnetic field imaging... spot defects in diamonds, jewellery, construction materials... biomedical sensor... negative electron charge, and holes with positive charge... both have spin... measuring signal change flip-flop to detect strength of magnetic field... details on sub-micron length scales... doesn’t require laser input... increase the field sensitivity"