Atomically flat surface preparation for surface-sensitive technologies

Tang Cen-Yao^{1, 2}, Rao Zhi-Cheng^{1, 2}, Yuan Qian-Qian^{3, 4}, Tian Shang-Jie⁵, Li Hang^{1, 2}, Huang Yao-Bo⁶, Lei He-Chang⁵, Li Shao-Chun^{3, 4}, Qian Tian^{1, 7}, Sun Yu-Jie^{1, 7, ‡}, Ding Hong^{1, 7}

(a) ARPES map of CoSi (001) surface BZ after grind-polish-sputter-anneal process at 110 eV, (b) cut along k_y = 0.67 π/a as indicated in panel (a) through Fermi arc surface state, (c) bulk band at R point measured at 435 eV, and (d) bulk band of CoSi by mechanical cleave.