WO 3-xFx（x < 0.45）类钙钛矿氟氧化物通过使用聚合物聚四氟乙烯（Teflon）的化学还原氢化路线制备。随着氟含量的增加，WO 3-xFx晶体结构的对称性由单斜→四方→立方。氟掺杂使绝缘的WO_3转变为金属导体，在氟含量为0.41 < x < 0.45的样品中发现了超导性（Tc = 0.4K）。这种简单的超导方法可能适用于其他系统，并为寻找新的氟氧化物超导体提供了机会。
英文摘要：
WO3-xFx (x < 0.45) perovskite-like oxyfluorides were prepared by a chemically reducing fluorination route using the polymer polytetrafluoroethylene (Teflon). The symmetry of the crystal structures of WO3-xFx changes from monoclinic to tetragonal to cubic as the fluorine content increases. Fluorine doping changes insulating WO3 to a metallic conductor, and superconductivity (Tc = 0.4 K) was discovered in the samples with fluorine contents of 0.41 < x < 0.45. This easy fluorination method may be applicable to other systems and presents an opportunity for finding new oxyfluoride superconductors.
We present detailed studies of the superconductivity in high-pressure H3S. X-ray diffraction measurements show that cubic Im-3m H3S was synthesized from elemental sulfur and hydrogen donor ammonia borane (NH3BH3). Our electrical transport measurements confirm superconductivity with a transition temperature Tc = 197 K at 153 GPa. From the analysis of both the normal state resistivity and the slope of the critical field, we conclude that the superconductivity is described by clean-limit behaviour. A significant broadening of the resistive transition in finite magnetic field is found, as expected…
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Superconducting dome and field-enhanced superconductivity of PLD synthesized Nd1-xEuxNiO2 thin films
Beijing National Laboratory for Condensed Matter Physics and Institute of Physics, Chinese Academy of Sciences（中国科学院物理研究所，北京凝聚态物理国家研究中心）；School of Physics and Astronomy, Beijing Normal University（北京师范大学物理与天文学院）；School of Physical Sciences, University of Chinese Academy of Sciences（中国科学院大学物理科学学院）；Key Laboratory of Multiscale Spin Physics, Ministry of Education, Beijing Normal University（北京师范大学多尺度自旋物理教育部重点实验室）
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We report superconductivity in as synthesized Nb2PdSe5, which is similar to recently discovered Nb2PdS5 compound having very high upper critical field, clearly above the Pauli paramagnetic limit [Sci. Rep. 3, 1446 (2013)]. A bulk polycrystalline Nb2PdSe5 sample is synthesized by solid state reaction route in phase pure structure. The structural characterization has been done by X ray diffraction, followed by Rietveld refinements, which revealed that Nb2PdSe5 sample is crystallized in monoclinic structure with in space group C2/m. Structural analysis revealed the formation of sharing of one dim…
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Possible high-Tc superconductivity at 45 K in the Ge-doped cluster Mott insulator GaNb4Se8
Institute of Physics and Beijing National Laboratory for Condensed Matter Physics, Chinese Academy of Sciences（中国科学院物理研究所与北京凝聚态物理国家实验室）；School of Physical Sciences, University of Chinese Academy of Sciences（中国科学院大学物理科学学院）
We synthesized lanthanum hydride (LaHx) by laser heating of lanthanum in hydrogen atmosphere at pressure P = 170 GPa. The sample shows a superconducting step at 209 K and 170 GPa and temperature dependence of resistance. By releasing the pressure to 150 GPa, the superconducting transition temperature Tc increases to 215 K - the record Tc. This finding supports a way of achieving Tc higher than the one in H3S (203 K) in hydrides with sodalite-like structures, first proposed for CaH6 (Tc=245 K) and later for yttrium and lanthanum hydrides where higher, room temperature superconductivity is expec…
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