Vacuum in optical cavity can change material's magnetic state without laser excitation

https://phys.org/news/2023-11-vacuum-optical-cavity-material-magnetic.html

"cavity vacuum fluctuations change magnetic order of α-RuCl3 from zigzag antiferromagnet into ferromagnet... quantum mechanical effect, vacuum is never really empty since light particles existence pop in and out affects material's properties... help realize new and elusive phases of matter, and better understand the delicate interplay between light and matter"

Related: Researchers demonstrate field-free switching of a commercial PMA ferromagnet at room temperature
https://techxplore.com/news/2023-11-field-free-commercial-pma-ferromagnet-room.html