<p>➀ Researchers discovered luminous quasiparticles (excitons) on the surface of the antiferromagnetic semiconductor CrSBr, challenging the belief that they could only exist within the material;</p><p>➁ Using ultrafast microscopy and spectroscopy, the team visualized surface excitons in ultra-thin crystal layers, noting distinct optical properties compared to internal excitons;</p><p>➂ The international collaboration highlights potential applications in energy storage, quantum information, and photonics-magnetism hybrid technologies.</p>