Figure 1 (IMAGE) Institute for Basic Science Caption Typical excitation patterns at different pack fractions. Reproduced from Fig.~1b-d of Nature, 11 November 2020 (online). Credit IBS Usage Restrictions Please indicate the credit. 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.