Comparative Study On Multifunctional Behavior Of La0.7ca0.24sr0.06mno3 And La0.88ca0.12mno3 Single Crystals

We have investigated electrical-transport, magneto-transport, magnetic and thermal properties of the hole doped La0.7Ca0.24Sr0.06MnO3 (LCSMO) and La0.88Ca0.12MnO3 (LCMO) single crystals, prepared using floating zone technique. The crystallographic direction dependence of metal to insulator transition (T-P) occurs at 290 K along c-axis and T-P = 280 K along oh-plane for LCSMO single crystal, while no electronic transition was observed over the whole temperature range under the magnetic field at 8 T for LCMO single crystal. Resistivity study shows that the T-P is higher along the c-axis as compared to that in the oh-plane, so signifying more favorable hoping of electrons is along the c-axis in LCSMO. The ac-susceptibility study confirms that these crystals, revealing ferromagnetic to paramagnetic transition temperature (T-C) at 277 K for LCSMO and T-C = 118 K for LCMO single crystals, which is close to the sharp peak around T-C in heat capacity data. For magneto-electric device application point of view, these crystals show the maximum MR of 80% and 65% for LCSMO and LCMO single crystals at 8 T applied magnetic field respectively.