Artificial antiphase boundary at the interface of ferrimagnetic spinel bilayers

${\text{CoFe}}_{2}{\text{O}}_{4}/{\text{Fe}}_{3}{\text{O}}_{4}$ bilayers represent an unusual exchange-coupled system whose properties are due to the nature of the oxide-oxide superexchange interactions at the interface. In this work, we analyze the magnetization reversal behavior and magnetic interface structure using a variety of advanced techniques. Low-temperature magnetization, magnetotransport, and polarized neutron reflectivity measurements suggest that the magnetization configuration at the bilayer interface mimics that of an antiphase boundary found in spinel ferrite thin films, thus explaining the unique nature of the magnetic behavior.