We synthesized large superconducting single crystal Ca0.77La0.18Fe0.90As2 ('112' type) of 2 millimeter size. Scanning electron microscopy (SEM) measurements revealed that bright and dark stripes alternately spread on the surface of crystals, indicating possible existence of intrinsic phase separation. Temperature (T) -dependent resistivity, Hall effect and magneto-resistance (MR) were measured with magnetic field (H) applied to different directions of crystal. The upper critical field (Hc2) anisotropy was estimated with a moderate value around 2.8. Positive Hall coefficient (RH) and anisotropic MR were found and showed strong T-dependent feature. Below T about 100 K, abnormal behaviors appear simultaneously in resistivity derivative, Hall coefficient and MR, which indicates that other scattering mechanisms more than conventional multiband effect may exist.
@article{arxiv.1312.7731,
title = {Possible Phase Separation and Transport Properties in Large Superconducting Ca0.77La0.18Fe0.90As2 Crystals},
author = {W. Zhou and J. C. Zhuang and F. F. Yuan and X. Li and Y. Sun and X. Z. Xing and Z. X. Shi},
journal= {arXiv preprint arXiv:1312.7731},
year = {2016}
}
Comments
This paper has been withdrawn by the author due to a crucial sign error of the Hall coefficient