Figure 1 (IMAGE) Institute for Basic Science Caption Two examples of “quantum phones”, both charged by quantum batteries based on electromagnetic fields. On the left, a charging protocol not using a micromaser approach leads to uncontrolled battery charging with possible damages. On the right, a charging protocol based on micromasers is able to self-control the amount of charge deposited into the quantum phone. Credit Institute for Basic Science Usage Restrictions Attribution Required 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.