Abstract
Topological insulators (TIs) are characterized by a non-trivial band topology driven by the spin-orbit coupling.
To fully explore the fundamental science and application of TIs, material realization is indispensable.
Here we predict, based on tight-binding modeling and first-principles calculations,
that bilayers of perovskite-type transition-metal oxides grown along the [111] crystallographic axis
are potential candidates for two-dimensional TIs.
The topological band structure of these materials can be fine-tuned by changing dopant ions, substrates and external gate voltages.
We predict that LaAuO$_3$ bilayers have a topologically non-trivial energy gap of about 0.15~eV,
which is sufficiently large to realize the quantum spin Hall effect at room temperature.
Intriguing phenomena, such as fractional quantum Hall effect,
associated with the nearly flat topologically non-trivial bands found in $e_g$ systems are also discussed.
