Artist's impression of bilayer graphene (IMAGE) Forschungszentrum Juelich Caption Artist's impression of bilayer graphene with an electron-hole symmetric double quantum dot, where the electron and the hole are in different layers. Credit Sebastian Staacks Usage Restrictions Editorial use permitted with credit to source. License Original 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.