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Temperature dependent orbital degree of freedom in a bilayer manganite by magnetic Compton scattering

Yinwan Li·P. A. Montano·J. F. Mitchell·B. Barbiellini·P. E. Mijnarends·S. Kaprzyk·A. Bansil
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Abstract

We have measured temperature-dependent magnetic Compton profiles (MCPs) from a single crystal of La$_{1.2}$Sr$_{1.8}$Mn$_2$O$_7$. The MCPs, which involved the scattering of circularly polarized x-rays, are in general related to the momentum density of all the unpaired spins in the system. Nevertheless, we show that when the x-ray scattering vector lies along the [110] direction, the number of magnetic electrons of a specific symmetry, i.e. $d$-electrons of $x^2-y^2$ symmetry, yield a distinct signature in the MCP, allowing us to monitor substantial changes in the occupancy of the $d_{x^2-y^2}$ states over the investigated temperature range of 5-200K. This study indicates that magnetic Compton scattering can provide a powerful window on the properties of specific magnetic electrons in complex materials.

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Yinwan Li, P. A. Montano, J. F. Mitchell, B. Barbiellini, P. E. Mijnarends, S. Kaprzyk, A. Bansil. 2004-10-21. Temperature dependent orbital degree of freedom in a bilayer manganite by magnetic Compton scattering. https://doi.org/10.1103/physrevlett.93.207206

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