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Magnetic susceptibility of the body-centred orthorhombic La$_2$CuO$_4$ system

Kyrylo V Tabunshchyk·R J Gooding
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Abstract

A model Hamiltonian representing the Cu spins in La$_2$CuO$_4$ in its low-temperature body-centred orthorhombic phase, that includes both spin-orbit generated Dzyaloshinskii-Moriya interactions and interplanar exchange, is examined within the RPA utilizing a Tyablikov decoupling of various high-order Green's functions. The magnetic susceptibility is evaluated as a function of temperature and the parameters quantifying these interactions, and compared to recently obtained experimental data of Lavrov, Ando and collaborators. An effective Hamiltonian corresponding to a simple tetragonal structure is shown to reproduce both the magnon spectra and the susceptibility of the more complicated body-centred orthorhombic model.

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Kyrylo V Tabunshchyk, R J Gooding. 2005-10-12. Magnetic susceptibility of the body-centred orthorhombic La$_2$CuO$_4$ system. https://doi.org/10.1088/0953-8984%2F17%2F42%2F010

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