SPIN SUSCEPTIBILITY IN THE LA2-XSRXCUO4 SYSTEM FROM UNDERDOPED TO OVERDOPED REGIMES

Cu-63 NMR Knight shifts were measured on La2-xSrxCuO4 for x=0.10, 0.16 , and 0.20 in the normal and superconducting states. These results, co mbined with magnetic susceptibility measurements, allow the separation of the carrier spin and orbital contributions to the susceptibility. At temperatures just above the superconducting transition, the conduct ion electron spin susceptibility increases dramatically with strontium doping. The analysis of the Knight shift at low temperature suggests that the spin susceptibility is zero and the superconducting state is a spin singlet.