Direct observation of localization of the minority-spin-band electrons in magnetite below the Verwey temperature

Two-dimensional spin-uncompensated momentum density distributions, ?s2D(p)s, were reconstructed in magnetite at 12 and 300 K from several measured directional magnetic Compton profiles. Mechanical detwinning was used to overcome severe twinning in the single-crystal sample below the Verwey transition. The reconstructed ?s2D(p) in the first...

Role of Oxygen Electrons in the Metal-Insulator Transition in the Magnetoresistive Oxide La2-2xSr1+2xMn2O7 Probed by Compton Scattering

We have studied the [100]-[110] anisotropy of the Compton profile in the bilayer manganite. Quantitative agreement is found between theory and experiment with respect to the anisotropy in the two metallic phases (i.e., the low temperature ferromagnetic and the colossal magnetoresistant phase under a magnetic field of 7 T). Robust signatures of...