2D Superconductivity in LSCO


  Gil Drachuck [1]  ,  Amit Keren [1]  ,  Meny Shay [1][2]  ,  Galina Bazalizki [1]  
[1] Technion
[2] Ort Braude College

We report direction dependent magnetization measurements in La2-xSrxCuO4 single crystals. The crystals were grown using traveling solvent floating zone method and were cut into rectangular needle-like shapes with the ā€cā€ direction parallel or perpendicular to the needle symmetry axis. The magnetic anisotropies were studied in details near the critical temperatures using a SQDUID magnetometer. The measurements were done at magnetic fields H<1Oe which is lower than the critical field Hc1 at T->Tc. A difference in Tc of 0.65 K was observed between parallel and perpendicular direction of the optimally doped samples (x=0.15). Higher anisotropy of 2.9 K was observed in under doped samples (x=0.08). We confirmed that the effect is not caused by sample inhomogeneity, needle dimensions, cooling rates, or misalignment. Our results indicate that there is a temperature region where La2-xSrxCuO4 behaves as a two dimensional superconductor.