Interface couplings in self-assembled nanostructures, especially in complex oxide composites, have been considered as a powerful tool to create and manipulate the lattice, charge, orbital, and spin degrees of freedoms.  Among various nanocomposites, vertical heteroepitaxial nanostructures with a high interface-to-volume ratio have become some of the most attractive systems because of their superior physical properties and designed functionalities through interfacial coupling, for example, strong and controllable magnetoelectric coupling in combinations of ferroelectric perovskites?ferromagnetic spinels (i.e., BaTiO₃?CoFe₂O₄, BiFeO₃ ?CoFe₂O₄ , etc . ), an abnormal dielectric response in BiFeO₃?Sm₂O₃, enhanced ferroelectricityin BaTiO₃?Sm₂O₃,and low magnetic-field drivencolossal magnetoresistance (CMR) in manganite-based nanocomposites.Our previous work had also manifested that aphoton-driven variation of magnetic pillars can be observed innanostructures composed of photostrictive SrRuO₃ (SRO) and magnetostrictive CoFe₂O₄ (CFO). This is a very fascinatingsystem since besides the presence of a photomagnetic effect,the transport behavior is another focal point we have tried todisclose. In this system, SRO is a well-known ?bad metal? oxidematerial, of which the resistivity shows a kink at its Curie temperature( T _C,SRO) ? 150 K for thin fi lm and ? 160 K for bulk). Unlike the perovskite manganites with CMR effect, SROdoes not show an impressive magnetoresistance (MR), which always requires a large field (above 3 Tesla (T)) and very lowtemperature (below 10 K) to achieve a value less than 10%. CFO is an insulator and can present a large strain-inducedmagnetic anisotropy while it forms the nanopillars embeddedin an SRO matrix. Therefore, our motivation is to create amodel system to see how the magnetic nanostructures directlyaffect the macroscopic transport behavior of the metallic matrix.The findings here are very attractive since they demonstratethat an unanticipated large MR effect ( ? 40% at 0.5T) at aroundthe Curie temperature of SRO ( T _C,SRO ) can be achieved in thisnon-manganite-based system. This work delivers a solution totrigger new functionalities in the strongly correlated systemsand therefore opens a new pathway to engineer and design thefunctionalities of heteroepitaxial oxide nanostructures.