Ultrastrong Purcell enhancement of magnetic dipole emission based on quasi-BIC Shu-Ling Cheng, Hong-Wei Wu and Yun-Qiao Yin Eur. Phys. J. D, 76 11 (2022) 211 Published online: 07 November 2022 DOI: 10.1140/epjd/s10053-022-00543-y