The ultrathinβ-Sn(001)films have attracted tremendous attention owing to its topological superconductivity(TSC),which hosts Majorana bound state(MBSs)for quantum computation.Recently,β-Sn(001)thin films have been su...The ultrathinβ-Sn(001)films have attracted tremendous attention owing to its topological superconductivity(TSC),which hosts Majorana bound state(MBSs)for quantum computation.Recently,β-Sn(001)thin films have been successfully fabricated via phase transition engineering.However,the understanding of structural phase transition ofβ-Sn(001)thin films is still elusive.Here,we report the direct growth of ultrathinβ-Sn(001)films epitaxially on the highly oriented pyrolytic graphite(HOPG)substrate and the characterization of intricate structural-transition-induced superstructures.The morphology was obtained by using atomic force microscopy(AFM)and low-temperature scanning tunneling microscopy(STM),indicating a structure-related bilayer-by-bilayer growth mode.The ultrathinβ-Sn film was made of multiple domains with various superstructures.Both high-symmetric and distorted superstructures were observed in the atomic-resolution STM images of these domains.The formation mechanism of these superstructures was further discussed based on the structural phase transition ofβtoα-Sn at the atomic-scale thickness.Our work not only brings a deep understanding of the structural phase transition of Sn film at the two-dimensional limit,but also paves a way to investigate their structure-sensitive topological properties.展开更多
Scanning probe microscopy(SPM)allows the spatial imaging,measurement,and manipulation of nano and atomic scale surfaces in real space.In the last two decades,numerous advanced and functional SPM methods,particularly a...Scanning probe microscopy(SPM)allows the spatial imaging,measurement,and manipulation of nano and atomic scale surfaces in real space.In the last two decades,numerous advanced and functional SPM methods,particularly atomic force microscopy(AFM),have been developed and applied in various research fields,from mapping sample morphology to measuring physical properties.Herein,we review the recent progress in functional AFM methods and their applications in studies of two-dimensional(2D)materials,particularly their interfacial physical properties on the substrates.This review can inspire more exciting application works using advanced AFM modes in the 2D and functional materials fields.展开更多
Transition-metal chalcogenides(TMCs)materials have attracted increasing interest both for fundamental research and industrial applications.Among all these materials,two-dimensional(2D)compounds with honeycomb-like str...Transition-metal chalcogenides(TMCs)materials have attracted increasing interest both for fundamental research and industrial applications.Among all these materials,two-dimensional(2D)compounds with honeycomb-like structure possess exotic electronic structures.Here,we report a systematic study of TMC monolayer AgTe fabricated by direct depositing Te on the surface of Ag(111)and annealing.Few intrinsic defects are observed and studied by scanning tunneling microscopy,indicating that there are two kinds of AgTe domains and they can form gliding twin-boundary.Then,the monolayer AgTe can serve as the template for the following growth of Te film.Meanwhile,some Te atoms are observed in the form of chains on the top of the bottom Te film.Our findings in this work might provide insightful guide for the epitaxial growth of 2D materials for study of novel physical properties and for future quantum devices.展开更多
基金Project supported by the National Natural Science Foundation of China(Grant Nos.61674045,61911540074,and 21622304)the Fund from the Ministry of Science and Technology of China(Grant No.2016YFA0200700)+1 种基金the Strategic Priority Research Program and Key Research Program of Frontier Sciences(Chinese Academy of Sciences)(Grant Nos.XDB30000000 and QYZDB-SSW-SYS031)Zhihai Cheng was supported by the Fundamental Research Funds for the Central Universities and the Research Funds of Renmin University of China(Grant No.21XNLG27).
文摘The ultrathinβ-Sn(001)films have attracted tremendous attention owing to its topological superconductivity(TSC),which hosts Majorana bound state(MBSs)for quantum computation.Recently,β-Sn(001)thin films have been successfully fabricated via phase transition engineering.However,the understanding of structural phase transition ofβ-Sn(001)thin films is still elusive.Here,we report the direct growth of ultrathinβ-Sn(001)films epitaxially on the highly oriented pyrolytic graphite(HOPG)substrate and the characterization of intricate structural-transition-induced superstructures.The morphology was obtained by using atomic force microscopy(AFM)and low-temperature scanning tunneling microscopy(STM),indicating a structure-related bilayer-by-bilayer growth mode.The ultrathinβ-Sn film was made of multiple domains with various superstructures.Both high-symmetric and distorted superstructures were observed in the atomic-resolution STM images of these domains.The formation mechanism of these superstructures was further discussed based on the structural phase transition ofβtoα-Sn at the atomic-scale thickness.Our work not only brings a deep understanding of the structural phase transition of Sn film at the two-dimensional limit,but also paves a way to investigate their structure-sensitive topological properties.
基金supported by the National Natural Science Foundation of China(NSFC)(Nos.61911540074,61674045,11604063,11622437,11974422,and 12172047)the Ministry of Science and Technology(MOST)of China(Nos.2016YFA0200700 and 2018YFE0202700)+1 种基金the support of the Strategic Priority Research Program of the Chinese Academy of Sciences(CAS)(No.XDB30000000)Z H C and W J received Fundamental Research Funds for the Central Universities and Research Funds of Renmin University of China(Nos.21XNLG27 and 19XNQ025).
文摘Scanning probe microscopy(SPM)allows the spatial imaging,measurement,and manipulation of nano and atomic scale surfaces in real space.In the last two decades,numerous advanced and functional SPM methods,particularly atomic force microscopy(AFM),have been developed and applied in various research fields,from mapping sample morphology to measuring physical properties.Herein,we review the recent progress in functional AFM methods and their applications in studies of two-dimensional(2D)materials,particularly their interfacial physical properties on the substrates.This review can inspire more exciting application works using advanced AFM modes in the 2D and functional materials fields.
基金This project was supported by the Ministry of Science and Technology(MOST)of China(No.2016YFA0200700)the National Natural Science Foundation of China(NSFC)(Nos.61674045 and 61911540074)+2 种基金the Strategic Priority Research Program and Key Research Program of Frontier Sciences(Chinese Academy of Sciences,CAS)(Nos.XDB30000000 and QYZDB-SSW-SYS031)Grant-in-Aid for Scientific Research from Japan Society for the Promotion of Science(JSPS)from the Ministry of Education,Culture,Sports,Science,and Technology of Japan(Nos.JP16H06327,JP16H06504,JP17H01061,and JP17H010610)Osaka University’s International Joint Research Promotion Program(Nos.J171013014,J171013007,J181013006,and Ja19990011).Z.H.C.was supported by the Fundamental Research Funds for the Central Universities and the Research Funds of Renmin University of China(No.21XNLG27).
文摘Transition-metal chalcogenides(TMCs)materials have attracted increasing interest both for fundamental research and industrial applications.Among all these materials,two-dimensional(2D)compounds with honeycomb-like structure possess exotic electronic structures.Here,we report a systematic study of TMC monolayer AgTe fabricated by direct depositing Te on the surface of Ag(111)and annealing.Few intrinsic defects are observed and studied by scanning tunneling microscopy,indicating that there are two kinds of AgTe domains and they can form gliding twin-boundary.Then,the monolayer AgTe can serve as the template for the following growth of Te film.Meanwhile,some Te atoms are observed in the form of chains on the top of the bottom Te film.Our findings in this work might provide insightful guide for the epitaxial growth of 2D materials for study of novel physical properties and for future quantum devices.
