Synthesis of large FeSe superconductor crystals via ion release/introduction and property characterization

作者：Dongna Yuan, Yulong Huang, Shunli Ni, Huaxue Zhou, Yiyuan Mao, Wei Hu, Jie Yuan, Kui Jin, Guang-Ming Zhang, Xiaoli Dong, Fang Zhou · 发表于：Chinese Physics B · 年份：2016 · DOI：10.1088/1674-1056/25/7/077404 · 被引用次数：19 · 研究领域：Iron-based superconductors research、Rare-earth and actinide compounds、Superconductivity in MgB2 and Alloys

Large superconducting FeSe crystals of (001) orientation have been prepared via a hydrothermal ion release/introduction route for the first time. The hydrothermally derived FeSe crystals are up to 10 mm × 5 mm × 0.3 mm in dimension. The pure tetragonal FeSe phase has been confirmed by x-ray diffraction (XRD) and the composition determined by both inductively coupled plasma atomic emission spectroscopy (ICP-AES) and energy dispersive x-ray spectroscopy (EDX). The superconducting transition of the FeSe samples has been characterized by magnetic and transport measurements. The zero-temperature upper critical field H c2 is calculated to be 13.2–16.7 T from a two-band model. The normal-state cooperative paramagnetism is found to be predominated by strong spin frustrations below the characteristic temperature T sn , where the Ising spin nematicity has been discerned in the FeSe superconductor crystals as reported elsewhere.