High-temperature superconductivity in sulfur hydride evidenced by alternating-current magnetic susce

• 作 者: Xiaoli Huang Xin Wang Defang Duan Bertil Sundqvist Xin Li Yanping Huang Hongyu Yu Fangfei Li Qiang Zhou Bingbing Liu Tian Cui
• 机 构: State Key Laboratory of Superhard Materials, College of Physics, Jilin University, Changchun 120012,
• 出 处: 国家科学评论（英文版）
• 发表日期: 2019年4期
• 关键词: high pressure hydrides superconductivity Meissner effect

The search for high-temperature superconductivity is one of the research frontiers in physics. In the sulfur hydride system, an extremely high Tc (～200 K) has been recently developed at pressure. However, the Meissner effect measurement above megabar pressures is still a great challenge. Here, we report the superconductivity identification of sulfur hydride at pressure, employing an in situ alternating-current magnetic susceptibility technique. We determine the superconducting phase diagram,finding that superconductivity suddenly appears at 117 GPa and Tc reaches 183 K at 149 GPa before decreasing monotonically with increasing pressure. By means of theoretical calculations, we elucidate the variation of Tc in the low-pressure region in terms of the changing stoichiometry of sulfur hydride and the further decrease in Tc owing to a drop in the electron–phonon interaction parameterλ. This work provides a new insight into clarifying superconducting phenomena and anchoring the superconducting phase diagram in the hydrides.