标题：Interplay of superconductivity and d-f correlation in CeFeAs1-xPxO1-yFy
作者：Luo Yong-Kang; Li Yu-Ke; Wang Cao; Lin Xiao; Dai Jian-Hui; Cao Guang-Han; Xu Zhu-An
作者机构：[Luo Yong-Kang; Li Yu-Ke; Wang Cao; Lin Xiao; Dai Jian-Hui; Cao Guang-Han; Xu Zhu-An] Zhejiang Univ, Dept Phys, Hangzhou 310027, Peoples R China.; [ 更多
通讯作者地址：[Xu, ZA]Zhejiang Univ, Dept Phys, Hangzhou 310027, Peoples R China.
来源：CHINESE PHYSICS B
关键词：superconductivity; iron-based pnictide; Kondo effect; heavy fermion;; quantum critical point; chemical pressure effect
摘要：The recent discovery of high-temperature superconductivity in iron-based pnictides (chalcogenides) not only triggers tremendous enthusiasm in searching for new superconducting materials, but also opens a new avenue to the study of the Kondo physics. CeFeAsO is a parent compound of the 1111-type iron-based superconductors. It shows 3d-antiferromagnetic (AFM) ordering below similar to 139 K and 4f-AFM ordering below similar to 4 K. On the other hand, the phosphide CeFePO is a ferromagnetically correlated heavy-fermion (HF) metal with Kondo scale T-K similar to 10 K. These properties set up a new platform for research of the interplay among magnetism, Kondo effect, and superconductivity (SC). In this review, we present the recent progress in the study of chemical pressure effect in CeFeAsO1-yFy (y = 0 and 0.05). This P/As-doping in CeFeAsO serves as an effective controlling parameter which leads to two magnetic critical points, x(c1) similar or equal to 0.4 and x(c2) similar or equal to 0.92, associated with suppression of 3d and 4f magnetism, respectively. We also observe a turning point of AFM-FM ordering of Ce3+ moment at x(c3) similar or equal to 0.37. The SC is absent in the phase diagram, which is attributed to the destruction to Cooper pair by Ce-FM fluctuations in the vicinity of x(c1). We continue to investigate CeFeAs1-xPxO0.95F0.05. With the separation of x(c1) and x(c3), this chemical pressure results in a broad SC region 0