Transport, thermal and magnetic properties of Ru1−xSbxSr2(Gd0.7Ce0.3)2Cu2O10−d

Abstract Electrical resistivity, Hall effect, heat capacity and magnetic susceptibility on Ru 1− x Sb x Sr 2 (Gd 0.7 Ce 0.3 ) 2 Cu 2 O 10− d system were investigated in the temperature range 4–300 K with a magnetic field up to 9 T. The structural analysis was investigated using X-ray diffraction. The resistivity transition temperature decreases from 41 K for x =0.00 to 18 K for x =0.06 Sb. This may be due to a distortion of RuO 6 octahedral, which is responsible of the increase in hole localization. Heat capacity, C ( T ), shows a jump at the superconducting transition temperature. Hall effect anomalies decrease below magnetic transition T m , which may be explained within a simple two-band model. The behavior of magnetic susceptibility is caused by antisymetric exchange coupling of the Dzyaloshinsky–Moriya (DM) type between neighboring Ru moments.