  In two-dimensional electron systems (2DES) the breaking of the inversion,
time-reversal and bulk crystal-field symmetries is interlaced with the effects
of spin-orbit coupling (SOC) triggering exotic quantum phenomena. Here, we used
epitaxial engineering to design and realize a 2DES characterized simultaneously
by ferromagnetic order, large Rashba SOC and hexagonal band warping at the
(111) interfaces between LaAlO$_{3}$, EuTiO$_{3}$ and SrTiO$_{3}$ insulators.
The 2DES displays anomalous quantum corrections to the magneto-conductance
driven by the time-reversal-symmetry breaking occurring below the magnetic
transition temperature. The results are explained by the emergence of a
non-trivial Berry phase and competing weak anti-localization / weak
localization back-scattering of Dirac-like fermions, mimicking the
phenomenology of gapped topological insulators. These findings open
perspectives for the engineering of novel spin-polarized functional 2DES
holding promises in spin-orbitronics and topological electronics.
