Single crystal growth and characterization of La2-xSrxCuO4 with Mn doping

A series of La(1.85)Sr(0.15)Cu(1-y)MnyO(4) (0 <= y <= 0.05) single crystal samples have for the first time been grown by the travel ling-solvent floating-zone method. Instead of preheating t. lie feed rod materials at intermediate temperatures, we directly preheat the starting materials at 1150 degrees C. After that we grow Mn doped samples at 0.33 mm/h, which is much slower than the widely adopted I Mm/h rate used in the single crystal growth of La2-xSrxCuO4 samples. We believe that these improvements are crucial for obtaining Mn substitution into La2-xSrxCuO4 without inducing impurity phases. The results of magnetic susceptibility measurements indicate that the onset superconducting transition temperature of Mn doped samples (0 <= y <= 0.025) does not decrease rapidly, indicating that Mn doping is quite peculiar compared to other elemental doping cases. (c) 2008 Elsevier B.V. All rights reserved.