Author(s): Mingxiang Pan, Feng Liu, and Huaqing Huang We introduce the concept of orbital altermagnetism, a symmetry-protected magnetic order of pure orbital degrees of freedom. It is characterized with ordered antiparallel orbital magnetic moments in real space but momentum-dependent orbital band splittings, analogous to spin altermagnetism. Using a m… [Phys. Rev. Lett. 137, 016702] Published Tue Jun 30, 2026