Zeng Shengwei, Tang Chi Sin, Yin Xinmao, Li Changjian, Li Mengsha, Huang Zhen, Hu Junxiong, Liu Wei, Omar Ganesh Ji, Jani Hariom, Lim Zhi Shiuh, Han Kun, Wan Dongyang, Yang Ping, Pennycook Stephen John, Wee Andrew T S, Ariando Ariando
Department of Physics, Faculty of Science, National University of Singapore, Singapore 117551, Singapore.
NUSNNI-NanoCore, National University of Singapore, Singapore 117411, Singapore.
Phys Rev Lett. 2020 Oct 2;125(14):147003. doi: 10.1103/PhysRevLett.125.147003.
Infinite-layer Nd_{1-x}Sr_{x}NiO_{2} thin films with Sr doping level x from 0.08 to 0.3 are synthesized and investigated. We find a superconducting dome x between 0.12 and 0.235 accompanied by a weakly insulating behavior in both under- and overdoped regimes. The dome is akin to that in the electron-doped 214-type and infinite-layer cuprate superconductors. For x≥0.18, the normal state Hall coefficient (R_{H}) changes the sign from negative to positive as the temperature decreases. The temperature of the sign changes decreases monotonically with decreasing x from the overdoped side and approaches the superconducting dome at the midpoint, suggesting a reconstruction of the Fermi surface with the dopant concentration across the dome.
合成并研究了锶掺杂水平x在0.08至0.3之间的无限层Nd₁₋ₓSrₓNiO₂薄膜。我们发现,在x介于0.12和0.235之间存在一个超导穹顶,同时在欠掺杂和过掺杂区域都伴有弱绝缘行为。该穹顶类似于电子掺杂的214型和无限层铜酸盐超导体中的穹顶。对于x≥0.18,随着温度降低,正常态霍尔系数(RH)从负变为正。符号变化的温度从过掺杂侧随着x的减小单调降低,并在中点处接近超导穹顶,这表明费米面随穹顶内掺杂浓度而重构。