Dynamical Structure Factor of Magnetic Excitation in Underdoped La_(1.9o)Sr_(o.1o)CuO_4 Measured by Chopper Neutron Spectrometer

摘要

We have performed inelastic neutron scattering measurement on high-transition temperature superconductor La_(1.9o)Sr_(o.1o)CuO_4 with utilizing a Fermi chopper spectrometer. We succeeded in converting the observed neutron scattering intensity into a dynamical structure factor in the absolute unit by attempting two methods with analyzing (i) incoherent scattering intensity from the sample itself and (ii) that from vanadium standard. The total squared moment was evaluated to be 0.176 μ.b /Cu, which is much smaller than the value for the parent compound, indicating a markedly change of electronic state by hole-doping.