中国物理B ›› 2016, Vol. 25 ›› Issue (9): 97402-097402.doi: 10.1088/1674-1056/25/9/097402
• CONDENSED MATTER: ELECTRONIC STRUCTURE, ELECTRICAL, MAGNETIC, AND OPTICAL PROPERTIES • 上一篇 下一篇
Nian Zhang(张念), Chen Liu(刘晨), Jia-Li Zhao(赵佳丽), Tao Lei(雷涛), Jia-Ou Wang(王嘉鸥), Hai-Jie Qian(钱海杰), Rui Wu(吴蕊), Lei Yan(颜雷), Hai-Zhong Guo(郭海中), Kurash Ibrahim(奎热西)
Nian Zhang(张念)1,2, Chen Liu(刘晨)1, Jia-Li Zhao(赵佳丽)1, Tao Lei(雷涛)1, Jia-Ou Wang(王嘉鸥)1, Hai-Jie Qian(钱海杰)1, Rui Wu(吴蕊)1, Lei Yan(颜雷)3, Hai-Zhong Guo(郭海中)3, Kurash Ibrahim(奎热西)1
摘要: A systematic investigation of oxidation on a superconductive FeTe0.5Se0.5 thin film, which was grown on Nb-doped SrTiO3 (001) by pulsed laser deposition, has been carried out. The sample was exposed to ambient air for one month for oxidation. Macroscopically, the exposed specimen lost its superconductivity due to oxidation. The specimen was subjected to in situ synchrotron radiation photoelectron spectroscopy (PES) and x-ray absorption spectroscopy (XAS) measurements following cycles of annealing and argon ion etching treatments to unravel what happened in the electronic structure and composition after exposure to air. By the spectroscopic measurements, we found that the as-grown FeTe0.5Se0.5 superconductive thin film experienced an element selective substitution reaction. The oxidation preferentially proceeds through pumping out the Te and forming Fe-O bonds by O substitution of Te. In addition, our results certify that in situ vacuum annealing and low-energy argon ion etching methods combined with spectroscopy are suitable for depth element and valence analysis of layered structure superconductor materials.
中图分类号: (Electronic structure (photoemission, etc.))