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, §}

Atomic structure of CuAs. (a) Close-up STM image of monolayer CuAs. The bright protuberances are extra As atoms. (I = 0.05 nA, V_b = –1 V). (b) Atomic resolution STM image of CuAs, clearly showing the honeycomb lattice. The black rhombus denotes a unit cell. (I = 5 nA, V_b = –20 mV). (c) Fully-relaxed atomic model of CuAs on Cu(111) substrate, depicting 3×3 superstructure. The black rhombus denotes a unit cell. (d) Side view of CuAs, showing the planner structure.