Condensed Spin Excitation of Quantized Dirac Fermions in the Quasi-Two-Dimensional Semimetal BaMnBi2RemoveMasashi Kumazaki, Azimjon Temurjonov, Takaaki Jinno, Yukihiro Watanabe, Taku Matsuhita, Yoshiaki Kobayashi, and Yasuhiro ShimizuPhys. Rev. Lett. 136, 106601 (2026)