Thumbnail
Access Restriction
Open

Author Wu, G. ♦ Chen, H. ♦ Xie, Y. L. ♦ Yan, Y. J. ♦ Wu, T. ♦ Liu, R. H. ♦ Wang, X. F. ♦ Fang, D. F. ♦ Ying, J. J. ♦ Chen, X. H.
Source arXiv.org
Content type Text
File Format PDF
Date of Submission 2008-06-10
Language English
Subject Domain (in DDC) Computer science, information & general works ♦ Natural sciences & mathematics ♦ Physics
Subject Keyword Condensed Matter - Superconductivity ♦ Condensed Matter - Materials Science ♦ physics:cond-mat
Abstract We synthesized Sr-doped $La_{0.85}Sr_{0.15}OFeAs$ sample with single phase, and systematically studied the effect of oxygen deficiency in the Sr-doped LaOFeAs system. It is found that substitution of Sr for La indeed induces the hole carrier evidenced by positive thermoelectric power (TEP), but no bulk superconductivity is observed. The superconductivity can be realized by annealing the as-grown sample in vacuum to produce the oxygen deficiency. With increasing the oxygen deficiency, the superconducting transition temperature ($T_c$) increases and maximum $T_c$ reaches about 26 K the same as that in La(O,F)FeAs. TEP dramatically changes from positive to negative in the nonsuperconducting as-grown sample to the superconducting samples with oxygen deficiency. While $R_H$ is always negative for all samples (even for Sr-doped as grown sample). It suggests that the $La_{0.85}Sr_{0.15}O_{1-\delta}FeAs$ is still electron-type superconductor.
Description Reference: Phys. Rev. B 78, 092503 (2008).
Educational Use Research
Learning Resource Type Article
Page Count 4


Open content in new tab

   Open content in new tab