We investigate the anisotropic magnetic transports in topological semimetal TaSb2. The compound shows the large magnetoresistance（MR） without saturation and the metal-insulator-like transition no matter whether the ...We investigate the anisotropic magnetic transports in topological semimetal TaSb2. The compound shows the large magnetoresistance（MR） without saturation and the metal-insulator-like transition no matter whether the magnetic field is parallel to c-axis or a-axis, except that the MR for B‖c is almost twice as large as that of B‖a at low temperatures. The adopted Kohler＇s rule can be obeyed by the MR at distinct temperatures for B‖c,but it is slightly violated as B‖a. The angle-dependent MR measurements exhibit the two-fold rotational symmetry below70 K,consistent with the monoclinic crystal structure of TaSb2. The dumbbell-like picture of angle-dependent MR in TaSb2 suggests a strongly anisotropic Fermi surface at low temperatures. However, it finally loses the two-fold symmetry over 70 K, implying a possible topological phase transition at around the temperature where Tm is related to a metal-insulator-like transition under magnetic fields.展开更多
We investigate the adsorption of organic molecular semiconductor perylene on(7×7)reconstructed Si(111)surface by ultraviolet photoemission spectroscopy.It is observed that seven features that derive from the orga...We investigate the adsorption of organic molecular semiconductor perylene on(7×7)reconstructed Si(111)surface by ultraviolet photoemission spectroscopy.It is observed that seven features that derive from the organic material are located at 0.71,2.24,4.0,5.9,7.46,8.65 and 9.95 eV in binding energy.The theoretical calculation results reveal the most stable adsorption geometry of organic molecule perylene on Si(111)(7×7)substrates is at the beginning of deposition.展开更多
基金Supported by the National Natural Science Foundation of China under Grant Nos 61401136,11604299 and 61376094the Zhejiang Natural Science Foundation of China under Grant No LY18F010019+1 种基金the Open Program from Wuhan National High Magnetic Field Center under Grant No 2016KF03the General Program of Natural Science Foundation of Jiangsu Province under Grant No BK20171440
文摘We investigate the anisotropic magnetic transports in topological semimetal TaSb2. The compound shows the large magnetoresistance（MR） without saturation and the metal-insulator-like transition no matter whether the magnetic field is parallel to c-axis or a-axis, except that the MR for B‖c is almost twice as large as that of B‖a at low temperatures. The adopted Kohler＇s rule can be obeyed by the MR at distinct temperatures for B‖c,but it is slightly violated as B‖a. The angle-dependent MR measurements exhibit the two-fold rotational symmetry below70 K,consistent with the monoclinic crystal structure of TaSb2. The dumbbell-like picture of angle-dependent MR in TaSb2 suggests a strongly anisotropic Fermi surface at low temperatures. However, it finally loses the two-fold symmetry over 70 K, implying a possible topological phase transition at around the temperature where Tm is related to a metal-insulator-like transition under magnetic fields.
基金the National Natural Science Foundation of China under Grant Nos.U1632102,11521404,11634009,11674222,11674226,11790313,11574202,11874256,11861161003 and 11874258the National Key Research and Development Program of China(Grant Nos.2016YFA0300403 and 2016YFA0301003)+1 种基金in part by the Key Research Program of the Chinese Academy of Science(Grant No.XDPB082)the Strategic Priority Research Program of Chinese Academy of Sciences(Grant No.XDB28000000).
文摘We investigate the adsorption of organic molecular semiconductor perylene on(7×7)reconstructed Si(111)surface by ultraviolet photoemission spectroscopy.It is observed that seven features that derive from the organic material are located at 0.71,2.24,4.0,5.9,7.46,8.65 and 9.95 eV in binding energy.The theoretical calculation results reveal the most stable adsorption geometry of organic molecule perylene on Si(111)(7×7)substrates is at the beginning of deposition.
