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

Yuan Dongna¹, Huang Yulong¹, Ni Shunli¹, Zhou Huaxue¹, Mao Yiyuan¹, Hu Wei¹, Yuan Jie¹, Jin Kui¹, Zhang Guangming³, Dong Xiaoli^{1, 2, †,}, Zhou Fang^{1, 2, ‡,}

(a) Powder XRD pattern for the FeSe crystal (T_c ∼ 7.6 K). All the diffraction peaks can be well indexed to the previously reported tetragonal unit cell with a = 3.7725(1) Å and c = 5.5247(2) Å. A small quantity (9.28 mg) of the sample was used for the XRD, so the signal-to-noise ratio is not high. (b) Double-crystal XRD rocking curve of the (003) reflection for the FeSe crystal. The surface dimension of the sample is 5 mm×1 mm.