  We describe a general materials design approach that produces large orbital
energy splittings (orbital polarization) in nickelate heterostructures,
creating a two-dimensional single-band electronic surface at the Fermi energy.
The resulting electronic structure mimics that of the high temperature cuprate
superconductors. The two key ingredients are: (i) the construction of
atomic-scale distortions about the Ni site via charge transfer and internal
electric fields, and (ii) the use of three component (tri-component)
superlattices to break inversion symmetry. We use {\it ab initio} calculations
to implement the approach, with experimental verification of the critical
structural motif that enables the design to succeed.
