Novel two-dimensional thermoelectric materials have attracted significant attention in the field of thermoelectric due to their low lattice thermal conductivity.A comprehensive understanding of their microscopic struc...Novel two-dimensional thermoelectric materials have attracted significant attention in the field of thermoelectric due to their low lattice thermal conductivity.A comprehensive understanding of their microscopic structures is crucial for driving further the optimization of materials properties and developing novel functional materials.Here,by using in situ scanning tunneling microscopy,we report the atomic layer evolution and surface reconstruction on the cleaved thermoelectric material KCu_(4)Se_(3) for the first time.We clearly revealed each atomic layer,including the naturally cleaved K atomic layer,the intermediate Se^(2-)atomic layer,and the Se^(-)atomic layer that emerges in the thermodynamic-stable state.Departing from the maj ority of studies that predominantly concentrate on macroscopic measurements of the charge transport,our results reveal the coexistence of potassium disorder and complex reconstructed patterns of selenium,which potentially influences charge carrier and lattice dynamics.These results provide direct insight into the surface microstructures and evolution of KCu_(4)Se_(3),and shed useful light on designing functional materials with superior performance.展开更多
We carried out experimental investigations of the geometric effect on the electronic behavior in Pb_(1-x)Bi_(x) thin films by scanning tunneling microscopy and spectroscopy.Single crystal monolayer Pb_(0.74)Bi_(0.26) ...We carried out experimental investigations of the geometric effect on the electronic behavior in Pb_(1-x)Bi_(x) thin films by scanning tunneling microscopy and spectroscopy.Single crystal monolayer Pb_(0.74)Bi_(0.26) and two-monolayer Pb_(0.75)Bi_(0.25)Pb_(1-x)Bi_(x) thin films were fabricated by molecular beam epitaxy,where large surface corrugations were observed.Combined with tunneling spectroscopic measurements,it is found that atomic corrugations can widely change the electronic behaviors.These findings show that the Pb_(1-x)Bi_(x) system can be a promising platform to further explore geometry-decorated electronic behavior in two-dimensional metallic thin films.展开更多
基金Project supported by the National Natural Science Foundation of China (Grant Nos.12374196,92165201,11634011,and 22109153)the Innovation Program for Quantum Science and Technology (Grant No.2021ZD0302800)+4 种基金the CAS Project for Young Scientists in Basic Research (Grant No.YSBR-046)the Fundamental Research Funds for the Central Universities (Grant Nos.WK3510000006 and WK3430000003)the Fund of Anhui Initiative in Quantum Information Technologies (Grant No.AHY170000)the University Synergy Innovation Program of Anhui Province,China (Grant No.GXXT-2022-008)the National Synchrotron Radiation Laboratory Joint Funds of University of Science and Technology of China (Grant No.KY2060000241)。
文摘Novel two-dimensional thermoelectric materials have attracted significant attention in the field of thermoelectric due to their low lattice thermal conductivity.A comprehensive understanding of their microscopic structures is crucial for driving further the optimization of materials properties and developing novel functional materials.Here,by using in situ scanning tunneling microscopy,we report the atomic layer evolution and surface reconstruction on the cleaved thermoelectric material KCu_(4)Se_(3) for the first time.We clearly revealed each atomic layer,including the naturally cleaved K atomic layer,the intermediate Se^(2-)atomic layer,and the Se^(-)atomic layer that emerges in the thermodynamic-stable state.Departing from the maj ority of studies that predominantly concentrate on macroscopic measurements of the charge transport,our results reveal the coexistence of potassium disorder and complex reconstructed patterns of selenium,which potentially influences charge carrier and lattice dynamics.These results provide direct insight into the surface microstructures and evolution of KCu_(4)Se_(3),and shed useful light on designing functional materials with superior performance.
基金Project supported by the National Key Basic Research Program of China(Grant No.2017YFA0205004)the National Natural Science Foundation of China(Grant Nos.92165201,11474261,and 11634011)+1 种基金the Fundamental Research Funds for the Central Universities(Grant No.WK3510000006)the Anhui Initiative Fund in Quantum Information Technologies(Grant No.AHY170000)。
文摘We carried out experimental investigations of the geometric effect on the electronic behavior in Pb_(1-x)Bi_(x) thin films by scanning tunneling microscopy and spectroscopy.Single crystal monolayer Pb_(0.74)Bi_(0.26) and two-monolayer Pb_(0.75)Bi_(0.25)Pb_(1-x)Bi_(x) thin films were fabricated by molecular beam epitaxy,where large surface corrugations were observed.Combined with tunneling spectroscopic measurements,it is found that atomic corrugations can widely change the electronic behaviors.These findings show that the Pb_(1-x)Bi_(x) system can be a promising platform to further explore geometry-decorated electronic behavior in two-dimensional metallic thin films.