Epitaxial fabrication of monolayer copper arsenide on Cu(111)

Zhang Shuai¹, Song Yang¹, Li Jin Mei², Wang Zhenyu¹, Liu Chen², Wang Jia-Ou², Gao Lei³, Lu Jian-Chen³, Zhang Yu Yang^{1, 4}, Lin Xiao^{1, 4, †}, Pan Jinbo^{1, ‡}, Du Shi Xuan^{1, 4}, Gao Hong-Jun^{1, 4, §}

STM, LEED, and XPS spectra of monolayer CuAs on a Cu(111) substrate. (a) LEED pattern of CuAs on Cu(111). White arrow denotes patterns from Cu(111), and red arrow denotes the diffraction spots of CuAs. (b) Large-area STM image of CuAs. (I = 0.05 nA, V_b = -1 V) (c) High-resolution XPS spectrum for As 3d. Two prominent peaks locate at 41.06 eV (As 3 d_5/2) and 41.69 eV (As 3 d_3/2). (d) XPS spectrum from the core level of Cu 2p. The peak at 932.4 eV is indicative of Cu 2p_3/2.