Fig. 2: Workflow for the construction of the unconventional magnon database.
From: Unconventional magnons in collinear magnets dictated by spin space groups
a, First, 1,223 collinear magnets were identified from the MAGNDATA database. Second, after the identification of the SSG, co-irrep screenings were performed to obtain the material candidates hosting unconventional magnons. Third, high-throughput calculations were performed to obtain all bilinear exchange interactions. Finally, an unconventional-magnon database with 203 magnon band structures and identified band representations was constructed. b, Statistics of five types of unconventional magnon in the collinear magnets from the MAGNDATA database, including: (1) chiral quasiparticles (C ≠ 0), including C-4 octuple, C-4 sextuple, C-8 Dirac and C-2 triple magnons; (2) topological charge-neutral (C = 0) quasiparticles, including duodecuple, octuple, sextuple and triple magnons; (3) octuple nodal line magnons; (4) quadruple nodal plane magnons; and (5) altermagnetic-splitting chiral magnons.