Abstract
We use resonant soft–x-ray scattering (RSXS) to study the electronic reconstruction at the interface between the Mott insulator and the band insulator . Superlattices of these two insulators were shown previously to have both ferromagnetism and metallic tendencies [Koida et al., Phys. Rev. B 66, 144418 (2002)]. By studying a judiciously chosen superlattice reflection, we show that the interface density of states exhibits a pronounced peak at the Fermi level, similar to that predicted in related titanate superlattices by Okamoto et al. [Phys. Rev. B 70, 241104(R) (2004)]. The intensity of this peak correlates with the conductivity and magnetization, suggesting it is the driver of metallic behavior. Our study demonstrates a general strategy for using RSXS to probe the electronic properties of heterostructure interfaces.
- Received 31 May 2007
DOI:https://doi.org/10.1103/PhysRevLett.99.196404
©2007 American Physical Society