Possible p-Wave Superconductivity in Epitaxial Bi/Ni Bilayers
GONG Xin-Xin1,2, ZHOU He-Xin1,2, XU Peng-Chao1,2, YUE Di1,2, ZHU Kai1,2, JIN Xiao-Feng1,2**, TIAN He3, ZHAO Ge-Jian4, CHEN Ting-Yong4
1State Key Laboratory of Surface Physics, and Department of Physics, Fudan University, Shanghai 200433 2Collaborative Innovation Center of Advanced Microstructures, Fudan University, Shanghai 210433 3State Key Laboratory of Silicon Materials and School of Materials Science and Engineering, Zhejiang University, Hangzhou 310027 4Department of Physics, Arizona State University, Tempe, AZ 85287, USA
Superconductivity (SC) is one of the most intriguing physical phenomena in nature. Nucleation of SC has long been considered highly unfavorable if not impossible near ferromagnetism, in low dimensionality and, above all, out of non-superconductor. Here we report observation of SC with TC near 4 K in Ni/Bi bilayers that defies all known paradigms of superconductivity, where neither ferromagnetic Ni film nor rhombohedra Bi film is superconducting in isolation. This highly unusual SC is independent of the growth order (Ni/Bi or Bi/Ni), but highly sensitive to the constituent layer thicknesses. Most importantly, the SC, distinctively non-s pairing, is triggered from, but does not occur at, the Bi/Ni interface. Using point contact Andreev reflection, we show evidences that the unique SC, naturally compatible with magnetism, is triplet p-wave pairing.
2015, Vol. 32 
