  We introduce a system of stacked two-dimensional electron and hole gas layers
with Rashba spin orbit interaction and show that the tunnel coupling between
the layers induces a strong three- dimensional (3D) topological insulator
phase. At each of the two-dimensional bulk boundaries we find the spectrum
consisting of a single anistropic Dirac cone, which we show by analytical and
numerical calculations. Our setup has a unit-cell consisting of four tunnel
coupled Rashba layers and presents a synthetic strong 3D topological insulator
and is distinguished by its rather high experimental feasibility.
