We report the tip-induced superconductivity on the topological semimetal NbSb_(2), similar to the observation on TaAs_(2) and NbAs_(2). Belonging to the same family of MPn_(2), all these materials possess similar band...We report the tip-induced superconductivity on the topological semimetal NbSb_(2), similar to the observation on TaAs_(2) and NbAs_(2). Belonging to the same family of MPn_(2), all these materials possess similar band structures, indicating that the tip-induced superconductivity may be closely related to their topological nature and share a common mechanism. Further analysis suggests that a bulk band should play the dominant role in such local superconductivity most likely through interface coupling. In addition, the compatibility between the induced superconductivity and tips’ ferromagnetism gives an evidence for its unconventional nature. These results provide further clues to elucidate the mechanism of the tip-induced superconductivity observed in topological materials.展开更多
HfMgMo（3-x）WxO（12） with x = 0.5, 1.0, 1.5, 2.0, and 2.5 are developed with a simple solid state method. With increasing the content of W, solid solutions of Hf Mg Mo3-xWx O12 crystallize in an orthorhombic structu...HfMgMo（3-x）WxO（12） with x = 0.5, 1.0, 1.5, 2.0, and 2.5 are developed with a simple solid state method. With increasing the content of W, solid solutions of Hf Mg Mo3-xWx O12 crystallize in an orthorhombic structure for x≤2.0 and a monoclinic structure for x2.0. A near-zero thermal expansion（ZTE） is realized for HfMgMo（2.5）W（0.5）O（12） and negative coefficients of thermal expansion（NCTE） are achieved for other compositions with different values. The ZTE and variation of NCTE are attributed to the difference in electronegativity between W and Mo and incorporation of a different amount of W, which cause variable distortion of the octahedra and softening of the MoO4 tetrahedra, and hence an enhanced NCTE in the a- and c-axis and reduced CTE in the b-axis as revealed by Raman spectroscopy and x-ray diffraction.展开更多
Using scanning tunneling microscopy we observe a stripe phase smoothly interfacing with a triangular 2 ×2 super- structure on the surface of 2H-NbSe2 single crystM. Proximity-induced superconductivity is demonstr...Using scanning tunneling microscopy we observe a stripe phase smoothly interfacing with a triangular 2 ×2 super- structure on the surface of 2H-NbSe2 single crystM. Proximity-induced superconductivity is demonstrated in these new ordered structures by measurements of low-temperature tunneling spectra. The modulation of superconduc- tivity by the reconstruction provides an opportunity to understand the interplay between superconductivity and charge orders.展开更多
基金Project supported by the National Key R&D Program of China(Grant Nos.2017YFA0302904,2017YFA0303201,2018YFA0305602,and 2016YFA0300604)the National Natural Science Foundation of China(Grants Nos.12074002,11574372,11674331,11804379,and 11874417)+4 种基金the National Basic Research Program of China(Grant No.2015CB921303)the Strategic Priority Research Program(B)of the Chinese Academy of Sciences(Grants Nos.XDB07020300,XDB07020100,and XDB33030100)the Collaborative Innovation Program of Hefei Science Center,the Chinese Academy of Sciences(Grant No.2020HSCCIP002)CASHIPS Director’s Fund,China(Grant No.BJPY2019B03)the Recruitment Program for Leading Talent Team of Anhui Province,China(2019-16)。
文摘We report the tip-induced superconductivity on the topological semimetal NbSb_(2), similar to the observation on TaAs_(2) and NbAs_(2). Belonging to the same family of MPn_(2), all these materials possess similar band structures, indicating that the tip-induced superconductivity may be closely related to their topological nature and share a common mechanism. Further analysis suggests that a bulk band should play the dominant role in such local superconductivity most likely through interface coupling. In addition, the compatibility between the induced superconductivity and tips’ ferromagnetism gives an evidence for its unconventional nature. These results provide further clues to elucidate the mechanism of the tip-induced superconductivity observed in topological materials.
基金supported by the National Natural Science Foundation of China(Grant Nos.10974183 and 11104252)the Key Natural Science Project of Henan Province,China(Grant No.142102210073)+1 种基金the Doctoral Fund of the Ministry of Education of China(Grant No.20114101110003)the Fund for Science & Technology Innovation Team of Zhengzhou,China(Grant No.112PCXTD337)
文摘HfMgMo（3-x）WxO（12） with x = 0.5, 1.0, 1.5, 2.0, and 2.5 are developed with a simple solid state method. With increasing the content of W, solid solutions of Hf Mg Mo3-xWx O12 crystallize in an orthorhombic structure for x≤2.0 and a monoclinic structure for x2.0. A near-zero thermal expansion（ZTE） is realized for HfMgMo（2.5）W（0.5）O（12） and negative coefficients of thermal expansion（NCTE） are achieved for other compositions with different values. The ZTE and variation of NCTE are attributed to the difference in electronegativity between W and Mo and incorporation of a different amount of W, which cause variable distortion of the octahedra and softening of the MoO4 tetrahedra, and hence an enhanced NCTE in the a- and c-axis and reduced CTE in the b-axis as revealed by Raman spectroscopy and x-ray diffraction.
基金Supported by the National Natural Science Foundation of China under Grant Nos 11574372 and 11322432the 'Strategic Priority Research Program(B)' of the Chinese Academy of Sciences under Grant No XDB07020300
文摘Using scanning tunneling microscopy we observe a stripe phase smoothly interfacing with a triangular 2 ×2 super- structure on the surface of 2H-NbSe2 single crystM. Proximity-induced superconductivity is demonstrated in these new ordered structures by measurements of low-temperature tunneling spectra. The modulation of superconduc- tivity by the reconstruction provides an opportunity to understand the interplay between superconductivity and charge orders.
