(Top) acoustic phonons, where the movement of atoms is in phase (Bottom) optical phonons, where the movement of atoms is out-of-phase. Optical phonons can be excited by electromagnetic waves. https://www.researchgate.net/figure/Two-types-of-phonon-modes-in-crystalline-structure-up-acoustic-phonons-where-the_fig16_333337278
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Dynamic structure factor S(q,w) and dispersion curve inset for the Heisenberg ferromagnet on the simple cubic lattice with L20 at T 0.4 T c. The momentum transfer is in the 100 direction, that is, q (q,0,0), and the Brillouin zone boundary is at q.
https://courses.physics.illinois.edu/phys498art/sp2018/PHYS489ART_SC_KP.pdf
Phase diagrams (temperature versus chemical doping or pressure) for four classes of superconductors: hole-doped cuprates like YBa2Cu3O6+x (upper left) [26], κ-(ET)2Cu[N(CN)2]Cl, a 2D-organic (upper right) [27], heavy fermion CeRhIn5 (lower left) [28], and an iron pnictide, Co-doped BaFe2As2 (lower right) [29].