Evolution of the Phase Diagram of LaFeP\(_{1-x}\)As\(_{x}\)O\(_{1-y}\)F\(_{y}\) (\(y\) = 0 -- 0.1)

• Published in: arXiv.org
• Main Authors: Lai, K T, Takemori, A, Miyasaka, S, Engetsu, F, Mukuda, H, Tajima, S
• Format: Paper
• Language: English
• Published: Ithaca Cornell University Library, arXiv.org 04.08.2014
• Subjects: Antiferromagnetism; Domes; Fermi surfaces; Phase diagrams; Transport properties
• ISSN: 2331-8422
• DOI: 10.48550/arxiv.1408.0584

P/As-substitution effects on the transport properties of polycrystalline LaFeP\(_{1-x}\)As\(_{x}\)O\(_{1-y}\)F\(_{y}\) with \(x\) = 0 -- 1.0 and \(y\) = 0 -- 0.1 have been studied. In the F-free samples (\(y\) = 0), a new superconducting (SC) dome with a maximum \(T_{c}\) of 12 K is observed around \(x\) = 0 -- 0.3. This is separated from another SC dome with \(T_{c}\) \(\sim\)10 K at \(x\) = 0.6 -- 0.8 by an antiferromagnetic region (\(x\) = 0.3 -- 0.6), giving a two-dome feature in the \(T_{c}-x\) phase diagram. As \(y\) increases, the two SC domes merge together, changing to a double peak structure at \(y\) = 0.05 and a single dome at \(y\) = 0.1. This proves the presence of two different Fermi surface states in this system.