Volume 83, Number 5, September 2008
Article Number 57002
Number of page(s) 4
Section Condensed Matter: Electronic Structure, Electrical, Magnetic and Optical Properties
Published online 06 August 2008
EPL, 83 (2008) 57002
DOI: 10.1209/0295-5075/83/57002

Pressure effect on superconductivity of iron-based arsenic-oxide ReFeAsO0.85 (Re = Sm and Nd)

Wei Yi, Liling Sun, Zhian Ren, Wei Lu, Xiaoli Dong, Hai-jun Zhang, Xi Dai, Zhong Fang, Zhengcai Li, Guangcan Che, Jie Yang, Xiaoli Shen, Fang Zhou and Zhongxian Zhao

Institute of Physics and Beijing National Laboratory for Condensed Matter Physics, Chinese Academy of Sciences - Beijing 100190, PRC

received 2 July 2008; accepted in final form 24 July 2008; published September 2008
published online 6 August 2008

Here we report pressure effects on the superconducting transition temperature $(T_{{\rm c}})$ of the ReFeAsO0.85 (Re = Sm and Nd) system without fluorine doping. In situ measurements under high pressure showed that $T_{{\rm c}}$ of the two compounds decreases monotonously over the pressure range investigated. The pressure coefficients ${\rm d}T_{{\rm c}}/{\rm d}P$ in SmFeAsO0.85 and NdFeAsO0.85 were different, revealing the important influence of the deformation in layers on $T_{{\rm c}}$. Theoretical calculations suggested that the electron density of states decreases with increasing pressure, following the same trend of experimental data.

74.70.-b - Superconducting materials.
62.50.-p - High-pressure effects in solids and liquids.

© EPLA 2008