학술논문
Hall-plot of the phase diagram for Ba(Fe1-xCox)2As2
Document Type
Working Paper
Author
Iida, Kazumasa; Grinenko, Vadim; Kurth, Fritz; Ichinose, Ataru; Tsukada, Ichiro; Ahrens, Eike; Pukenas, Aurimas; Chekhonin, Paul; Skrotzki, Werner; Teresiak, Angelika; Huehne, Ruben; Aswartham, Saicharan; Wurmehl, Sabine; Moench, Ingolf; Erbe, Manuela; Haenisch, Jens; Holzapfel, Bernhard; Drechsler, Stefan-Ludwig; Efremov, Dmitri V.
Source
Scientific Reports 6, 28390 (2016)
Subject
Language
Abstract
The Hall effect is a powerful tool for investigating carrier type and density. For single-band materials, the Hall coefficient is traditionally expressed simply by $R_H^{-1} = -en$, where $e$ is the charge of the carrier, and $n$ is the concentration. However, it is well known that in the critical region near a quantum phase transition, as it was demonstrated for cuprates and heavy fermions, the Hall coefficient exhibits strong temperature and doping dependencies, which can not be described by such a simple expression, and the interpretation of the Hall coefficient for Fe-based superconductors is also problematic. Here, we investigate thin films of Ba(Fe$_{1-x}$Co$_x$)$_2$As$_2$ with compressive and tensile in-plane strain in a wide range of Co doping. Such in-plane strain changes the band structure of the compounds, resulting in various shifts of the whole phase diagram as a function of Co doping. We show that the resultant phase diagrams for different strain states can be mapped onto a single phase diagram with the Hall number. This universal plot is attributed to the critical fluctuations in multiband systems near the antiferromagnetic transition, which may suggest a direct link between magnetic and superconducting properties in the BaFe$_2$As$_2$ system.
Comment: Accepted for publication in Scientific Reports, 6 main figures plus Supplemental Information (8 figures)
Comment: Accepted for publication in Scientific Reports, 6 main figures plus Supplemental Information (8 figures)