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arXiv · 1302.5155

Superconductivity induced by U-doping in the SmFeAsO system

Bo Huang·Jijun Yang·Jun Tang·Jiali Liao·Yuanyou Yang·Ning Liu·Gang Mu·Tao Hu·Xiaoping Shen·Donglai Feng
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Abstract

Through partial substitution of Sm by U in SmFeAsO, a different member of the family of iron-based superconductors was successfully synthesized. X-ray diffraction measurements show that the lattice constants along the a and c axes are both squeezed through U doping, indicating a successful substitution of U at the Sm site. The parent compound shows a strong resistivity anomaly near 150 K, associated with spin-density-wave instability.U doping suppresses this instability and leads to a transition to the superconducting state at temperatures up to 49 K. Magnetic measurements confirm the bulk superconductivity in this system. For the sample with a doping level of x = 0.2, the external magnetic field suppresses the onset temperature very slowly, indicating a rather high upper critical field. In addition, the Hall effect measurements show that U clearly dopes electrons into the material.

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Bo Huang, Jijun Yang, Jun Tang, Jiali Liao, Yuanyou Yang, Ning Liu, Gang Mu, Tao Hu, Xiaoping Shen, Donglai Feng. 2013-02-21. Superconductivity induced by U-doping in the SmFeAsO system. https://doi.org/10.1103/physrevb.87.060501

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