Extracting d-orbital occupancy from magnetic Compton scattering in bilayer manganites
نویسندگان
چکیده
We consider the shape of the magnetic Compton profile (MCP), Jmag(pz), in La1.2Sr1.8Mn2O7 for momentum transfer pz along the [110] direction and the associated reciprocal form factor B(r) defined by taking the one-dimensional Fourier transform of Jmag(pz). B(r) is shown to contain a prominent dip at rz1 Å, where the minimum value Bmin of B(r) can be related to the occupancies of the eg orbitals of dx2Ky2 and d3z2Kr2 symmetry in the system. We illustrate our procedure in detail by analyzing the measured MCP at 5 K and the MCP computed within the framework of the local spin density approximation (LSDA) and comment on the differences between the measured and computed eg occupancies as a reflection of the limitations of the LSDA in treating electron correlation effects. q 2005 Elsevier Ltd. All rights reserved.
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Temperature-dependent orbital degree of freedom of a bilayer manganite by magnetic compton scattering.
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