Reduction of ordered moment in strongly correlated LaTiO_3+δupon band filling

Abstract

Neutron diffraction and magnetic susceptibility experiments were performed on single crystals of the doped Mott-Hubbard insulator LaTiO3+δ. The magnetic properties of the three-dimensional correlated electron system were investigated upon hole doping. The size of the ordered moment of Ti3+ in the canted antiferromagnetically ordered phase reaches a maximum of 0.46(2)μB for LaTiO3. Upon increasing the band filling, i.e., upon increasing the amount of nonstoichiometric oxygen d from 0 to 0.08, the ordered moment on Ti3+ is shown to decrease rapidly. The weak-ferromagnetic saturation moment of LaTiO3.07(1), on the verge of the insulator-to-metal transition, is reached via a series of steps in the magnetization curve. © 1999 The American Physical Society.