“…[30][31][32][33][34][35][36][37][38][39][40][41][42] Interestingly, in this system H E values ranging from a few to thousands of Oe have been reported for relatively similar nanoparticles. Several effects have been reported to influence HE in Co/CoO: core diameter, 34,39,40 shell thickness, 34,37,39,40 crystallinity of the shell, 32,43,44 exchange interactions with neighboring particles, 32,45 strains, 34 orbital moments, 45 uncompensated spins 33,41 and the matrix they are embedded in (through lattice matching effects or antiferromagnetic proximity effects). 31,33,36,46 Concerning the role of the matrix in Co/CoO, HE values extending from 10 Oe (in non-AFMnon-lattice matched matrices, e.g., Al2O3 ) 31 to 7500 Oe (in AFMlattice matched matrices, e.g., CoO) 31,36 have been reported for rather similar nanoparticles.…”