| Abstrakt: |
SmNiO 3 is a representative quantum material exhibiting the antidoping behavior, where the conductivity of the material is reduced rather than increased by electron doping. Recent experimental and theoretical works have demonstrated a phase transition of SmNiO 3 with large conductance changes via chemical methods. However, the effect of electron doping via interfacial charge transfer in SmNiO 3 is much less studied. In this work, the first-principles density functional theory (DFT)+ U method is employed to investigate the SmNiO 3 /YTiO 3 superlattice, in which the YTiO 3 layer acts as the electron donor. Compared with the chemical doping in SmNiO 3 , several interesting physical phenomena have been predicted in SmNiO 3 /YTiO 3 superlattices due to the lattice and electronic reconstructions. First, at a doping concentration of 1 e − per Ni, i.e., (SmNiO 3) 1 /(YTiO 3) 1 superlattice, all Ni 3 + are converted to Ni 2 + , resulting in a Mott-insulating phase, similar to the chemical doping in the pristine material. Interestingly, such a Mott gap can be efficiently modulated by tuning the stacking orientation. Second, at a doping concentration of 1 2 e − per Ni, i.e., [ 001 ]-orientated (SmNiO 3) 2 /(YTiO 3) 1 superlattice, the electronic structure associated with charge ordering depends on the concrete magnetic order, giving rise to magnetism-dependent electronic behavior. In addition, as the doping concentration further decreases (i.e., a doping concentration of 1 3 e − /Ni), a metallic state is predicted in a [ 001 ]-orientated (SmNiO 3) 3 /(YTiO 3) 1 superlattice, which is quite different from the case of chemical doping. [ABSTRACT FROM AUTHOR] |
