Extracting d-orbital occupancy from magnetic Compton scattering in bilayer manganites

Abstract

We consider the shape of the magnetic Compton profile (MCP), $J_{mag}(p_z)$, in La${}_{1.2}$Sr${}_{1.8}$Mn${}_2$O${}_7$ for momentum transfer $p_z$ along the [110] direction and the associated reciprocal form factor $B(r)$ defined by taking the one-dimensional Fourier transform of $J_{mag}(p_z)$. $B(r)$ is shown to contain a prominent dip at $r\approx$ 1 $\mathring{A}$, where the minimum value $B_{min}$ of $B(r)$ can be related to the occupancies of the $e_g$ orbitals of $d_{x^2-y^2}$ and $d_{3z^2-r^2}$ symmetry in the system. We illustrate our procedure in detail by analyzing the measured MCP at 5K and the MCP computed within the framework of the local spin density approximation (LSDA) and comment on the differences between the measured and computed $e_g$ occupancies as a reflection of the limitations of the LSDA in treating electron correlation effects.

arXiv comment5 pages, 3 figures, to appear in J. Phys. Chem. Solids

References in corpus (5)

• Electronic structure and magnetism of Fe${}_{3-x}$V${}_x$X (X = Si, Ga and Al) alloys by the KKR-CPA method
• Compton scattering beyond the impulse approximation
• Re-examination of orbital ordering in LaMnO${}_3$: Electron-electron and electron-lattice interactions
• Temperature dependent orbital degree of freedom in a bilayer manganite by magnetic Compton scattering
• Coulomb correlation and magnetic ordering in double-layered manganites: LaSr${}_2$Mn${}_2$O${}_7$

Cited by in corpus (4)

• Role of Oxygen Electrons in the Metal-Insulator Transition in the Magnetoresistive Oxide La${}_{2-2x}$Sr${}_{1+2x}$Mn${}_2$O${}_7$ Probed by Compton Scattering
• Orbital mixing and nesting in the bilayer manganites La${}_{2-2x}$Sr${}_{1+2x}$Mn${}_2$O${}_7$
• Identification of ferrimagnetic orbitals preventing spinel degradation by charge ordering in Li${}_x$Mn${}_2$O${}_4$
• A Minimal tight-binding model for ferromagnetic canted bilayer manganites