Device (IMAGE) University of Würzburg Caption Until now, the zero magnetic field Quantum Anomalous Hall effect only occurred at very low currents. This device can change that. Credit Fijalkowski/JMU Usage Restrictions / 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.