Valley Splitting (IMAGE) Vienna University of Technology Caption The charged tip of a scanning tunneling microscope and an additional magnetic field lead to localized stable electron states in graphene. Credit Nils Freitag, RWTH Aachen Usage Restrictions None License Licensed content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.