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تسجيل مستخدم جديدQuantum-Confinement-Induced Magnetism in LaNiO$_3$-LaMnO$_3$ Superlattices
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The emergence of magnetic reconstructions at the interfaces of oxide heterostructures are often explained via subtle modifications in the electronic densities, exchange couplings, or strain. Here an additional possible route for induced magnetism is studied in the context of the (LaNiO$_3$)$_n$/(LaMnO$_3$)$_n$ superlattices using a hybrid tight-binding model. In the LaNiO$_3$ region, the induced magnetizations decouple from the intensity of charge leakage from Mn to Ni, but originate from the spin-filtered quantum confinement present in these nanostructures. In general, the induced magnetization is the largest for the (111)-stacking and the weakest for the (001)-stacking superlattices, results compatible with the exchange bias effects reported by Gibert et al. Nat. Mater. 11, 195 (2012).
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Motivated by recent experiments, we use the $+U$ extension of the generalized gradient approximation to density functional theory to study superlattices composed of alternating layers of LaNiO$_3$ and LaMnO$_3$. For comparison we also study a rocksal
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By combining ab initio simulations including an on-site Coulomb repulsion term and Boltzmann theory, we explore the thermoelectric properties of (LaNiO$_3$)$_n$/(LaAlO$_3$)$_n$(001) superlattices ($n=1,3$) and identify a strong dependence on confinem
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