Magnetic Susceptibility of High-Tc Superconducting Oxides (La, A)2CuO4 (A=Ba, Sr)

Magnetic properties of high- T c superconducting oxides (La, A) 2 CuO 4 (A=Sr, Ba) are investigated in both normal and superconducting states. The results indicate that these oxides belong to type II superconductor and that lower critical field H c 1 is estimated to be about 400 Oe at 4.7 K from magnetization measurements. It is found that these oxides show a paramagnetism of the order of 10 -7 emu/g in the normal state. Density of states at Fermi level is estimated from the magnetic susceptibility in the normal state.