  The exploration of exchange bias (EB) on the nanoscale provides a novel
approach to improving the anisotropic properties of magnetic nanoparticles for
prospective applications in nanospintronics and nanomedicine. However, the
physical origin of EB is not fully understood. Recent advances in chemical
synthesis provide a unique opportunity to explore EB in a variety of iron
oxide-based nanostructures ranging from core/shell to hollow and hybrid
composite nanoparticles. Experimental and atomistic Monte Carlo studies have
shed light on the roles of interface and surface spins in these nanosystems.
This review paper aims to provide a thorough understanding of the EB and
related phenomena in iron oxide-based nanoparticle systems, knowledge of which
is essential to tune the anisotropic magnetic properties of exchange-coupled
nanoparticle systems for potential applications.
