Quantum Physics2025-09-182 minarXiv:2509.14506Electron on Helium Catches a Microwave Photon for the First TimeAbove the mirror-like surface of superfluid helium cooled to 7 millikelvin, a single electron dances in perfect waltz with a microwave photon.G. Koolstra·E. O. Glen·N. R. Beysengulov·H. Byeon·K. E. Castoria·M. Sammon·S. A. Lyon·D. G. Rees·J. PollanenHendrik LorentzChristian DopplerAlbert EinsteinEHThelium👍👎☆SimplePopularAdvanced