Professor XIE, Maohai

Current Research

• Experimental Condensed Matter and Material Science Group: Materials Science - Experimental Surface Science
  • The surface science laboratory aims at understanding the processes and properties that occur at the boundary of materials - surface.
    Current researches focus on the growth and surface characterizations of low-dimensional materials, such as transition-metal dichalcogenides and their hetero-structures.
    We carry out molecular beam epitaxy (MBE) and surface studies of ultrathin layers MBE is one of the most versatile techniques to grow materials with precise control. It allows fabrication of artificial structures by combining different materials to form the so-called "quantum wells" and "superlattices". Quantum effects and new concepts in material sciences are thus explored for modern device applications. By using STM/S and UPS, we characterize the atomic and electronic structures of film surfaces. The latter are important for the understanding various quantum effects at atomic scale.

Research Interest

• Experimental Condensed Matter Physics
• Surface and Materials Science
• Molecular-beam Epitaxy
• Scanning Tunneling Microscopy
• Electron Diffraction
• Photoelectron Spectroscopy

Representative Publications

• “Wafer-scale single-crystalline MoSe₂ and WSe₂ monolayers grown by molecular-beam epitaxy at low-temperature — the role of island-substrate interaction and surface steps”, Yipu Xia, Degong Ding, Ke Xiao, Junqiu Zhang, Shaogang Xu, Daliang He, Xingyu Yue, Qing Rao, Xiong Wang, Sujuan Ding, Guoyun Gao, Hongxia Xue, Yueyang Wang, Mengfei Yuan, Wingkin Ho, Dong-Keun Ki, Hu Xu, Xiaodong Cui, Chuanhong Jin, Maohai Xie, Natural Sciences3, 20220059 (2023)
• “Charge Density Modulation and the Luttinger Liquid State in MoSe2 Mirror Twin Boundaries”, Yipu Xia, Junqiu Zhang, Yuanjun Jin, Wingkin Ho, Hu Xu, Maohai Xie, ACS Nano14, 10716 (2020)
• “Quantum Confined Tomonaga–Luttinger Liquid in Mo₆Se₆ Nanowires Converted from an Epitaxial MoSe₂ Monolayer”, Yipu Xia, Bo Wang, Junqiu Zhang, Yuanjun Jin, Hao Tian, Wingkin Ho, Hu Xu, Chuanhong Jin, Maohai Xie, Nano Lett.20, 2094 (2020)
• “Two-dimensional metal-phosphorus network”, Hao Tian, Jun-Qiu Zhang, Wingkin Ho, Jin-Peng Xu, Bowen Xia, Yipu Xia, Jing Fan, Hu Xu, Maohai Xie, SY Tong, Matter2, 111 (2020)
• “One-dimensional phosphorus chain and two-dimensional blue phosphorene grown on Au (111) by molecular-beam epitaxy”, J.P. Xu, J.Q. Zhang, H. Tian, H. Xu, W.K. Ho, M.H. Xie, Phys. Rev. Mater.1, 061002(R) (2017)
• “Ultrathin layers of b-tellurene grown on highly oriented pyrolytic graphite by molecular-beam epitaxy”, J.L. Chen, Y.W. Dai, Y.Q. Ma, X.Q. Dai, W.K. Ho, M.H. Xie, Nanoscale9, 15945-15948(2017)
• “Molecular-beam epitaxy of monolayer MoSe₂: growth characteristics and domain boundary formation”, L. Jiao, H. Liu, J. Chen, Y. Yi, W.G. Chen, Y. Cai, J.N. Wang, X.Q. Dai, N. Wang, W.K. Ho, M.H. Xie, New J. Physics17, 053023 (2015)
• “Observation of intervalley quantum interference in epitaxial monolayer WSe₂”, H. Liu, J. Chen, H. Yu, F. Yang, L. Jiao, G.B. Liu, W.K. Ho, C.L. Gao, J.F. Jia, W. Yao, M.H. Xie, Nat. Comm.6, 8180 (2015)
• “Dense network of one-dimensional midgap metallic modes in monolayer MoSe₂ and their spatial undulations”, H. Liu, L. Jiao, F. yang, Y. Cai, X.X. Wu, W.K. Ho, C.L. Gao, J.F. Jia, N. Wang, H. Fan, W. Yao, M.H. Xie, Phys. Rev. Lett.113, 066105 (2014)
• “Anisotropic topological surface states on high-index Bi₂Se₃ films”, Z. Xu, X. Guo, M.Y. yao, H.T. He, L. Miao, L. Jiao, H.C. Liu, J.N. Wang, D. Qian, J.F. Jia, W.K. Ho, M.H. Xie, Adv. Mater.25, 1557 (2013)