Science Daily  May 25, 2021 Exotic quantum vacuum phenomena are predicted in cavity quantum electrodynamics systems with ultra-strong light-matter interactions. However, such predictions have not been realized because antiresonant interactions are typically negligible compared to resonant interactions in light-matter systems. An international team of researchers (USA – Rice University, Japan, Germany, China) reports an unusual, ultra-strongly coupled matter-matter system of magnons that is analytically described by a unique Hamiltonian in which the relative importance of resonant and antiresonant interactions can be easily tuned and the latter can be made vastly dominant. They found a regime where vacuum Bloch-Siegert shifts, the […]