May 23, 2008 (H25). A group of Chinese authors reported in the latest paper published inSuperconductor Science and Technology (SuST) on the recently discovered FeAs-based superconducting compounds.
“Superconductivity at 53.5 K in GdFeAsO(1-δ)” by Z-A Ren et al. reports the fabrication and superconductivity of the iron-based arsenic-oxideGdFeAsO(1-δ) compound with oxygen-deficiency, which has an onset resistivity transition temperature of 53.5 K. This material has the same crystal structure as the high-Tc ReFeAsO1−δ family (Re = rare earth metal) newly discovered by Kamihara et al[1]. TheGdFeAsO(1-δ) has a further reduced crystal lattice, while the Tc is lower than in the SmFeAsO1−δsystem.
As a rapid communication, this SuST paper is permanently free for everyone to read at http://www.iop.org/EJ/toc/0953-2048/21/8
Fig. 1. The temperature dependence of the dc susceptibility and the differential ZFC curve for the nominal GdFeAsO0.85 sample synthesized by the high-pressure synthesis (HP) method.