Scanning tunneling microscopy is a powerful tool to build artificial atomic structures that do not exist in nature but possess exotic properties.In this study,we constructed Lieb lattices with different lattice consta...Scanning tunneling microscopy is a powerful tool to build artificial atomic structures that do not exist in nature but possess exotic properties.In this study,we constructed Lieb lattices with different lattice constants by real atoms,i.e.,Fe atoms on Ag(111),and probed their electronic properties.We obtain a surprising long-range effective electron wavefunction overlap between Fe adatoms as it exhibits a 1/r;dependence with the interatomic distance r instead of the theoretically predicted exponential one.Combining control experiments,tight-binding modeling,and Green’s function calculations,we attribute the observed long-range overlap to being enabled by the surface state.Our findings enrich the understanding of the electron wavefunction overlap and provide a convenient platform to design and explore artificial structures and future devices with real atoms.展开更多
Anisotropic localization of Dirac fermions in graphene along both the x and y axes was studied using the transfer-matrix method. The two-parameter scaled behavior around the Dirac points was observed along the x axis ...Anisotropic localization of Dirac fermions in graphene along both the x and y axes was studied using the transfer-matrix method. The two-parameter scaled behavior around the Dirac points was observed along the x axis with off-diagonal disorder. In contrast, the electronic state along the y axis with armchair edges was delocalized, which can be described well by single parameter scaling theory. This implies that the breakdown of the single-parameter scaling is related to the zigzag edge along the x axis. Furthermore, dimerization induced by the substrate suppresses the two-parameter scaling behavior along the x axis and preserves the delocalized state along the y axis. Our results also demonstrate anisotropic localization in graphene with diagonal disorder that can be tuned by dimerization.展开更多
基金supported by the National Key R&D Program of China(Grant Nos.2017YFA0303202 and 2018YFA0306004)the National Natural Science Foundation of China(Grant Nos.11974165,92165103,51971110,and 11734006)+1 种基金the China Postdoctoral Science Foundation(Grant No.2019M651766)the Natural Science Foundation of Jiangsu Province(Grant No.BK20190057)。
文摘Scanning tunneling microscopy is a powerful tool to build artificial atomic structures that do not exist in nature but possess exotic properties.In this study,we constructed Lieb lattices with different lattice constants by real atoms,i.e.,Fe atoms on Ag(111),and probed their electronic properties.We obtain a surprising long-range effective electron wavefunction overlap between Fe adatoms as it exhibits a 1/r;dependence with the interatomic distance r instead of the theoretically predicted exponential one.Combining control experiments,tight-binding modeling,and Green’s function calculations,we attribute the observed long-range overlap to being enabled by the surface state.Our findings enrich the understanding of the electron wavefunction overlap and provide a convenient platform to design and explore artificial structures and future devices with real atoms.
基金Project supported by the National Basic Research Program of China(Grant No.2010CB923404)the National Natural Science Foundation of China(Grant No.11021403)the National Science Fund for Distinguished Young Scholars of China(Grant No.10025419)
文摘Anisotropic localization of Dirac fermions in graphene along both the x and y axes was studied using the transfer-matrix method. The two-parameter scaled behavior around the Dirac points was observed along the x axis with off-diagonal disorder. In contrast, the electronic state along the y axis with armchair edges was delocalized, which can be described well by single parameter scaling theory. This implies that the breakdown of the single-parameter scaling is related to the zigzag edge along the x axis. Furthermore, dimerization induced by the substrate suppresses the two-parameter scaling behavior along the x axis and preserves the delocalized state along the y axis. Our results also demonstrate anisotropic localization in graphene with diagonal disorder that can be tuned by dimerization.
