The role of Cocation addition in enhancing the AC heat induction power of (CoMn)FeOsuperparamagnetic nanoparticles.

The physical role of magnetically semi-hard Cocation addition in enhancing the AC heat induction temperature () or specific loss power (SLP) of solid (CoMn)FeOsuperparamagnetic iron oxide nanoparticles (SPIONPs) was systematically investigated at the biologically safe and physiologically tolerable range of(= 1.12 × 10A ms,= 100 kHz,= 140 Oe (11.2 A m)) to demonstrate which physical parameter would be the most critical and dominant in enhancing the(SLP) of SPIONPs. According to the experimentally and theoretically analyzed results, it was clearly demonstrated that the enhancement of magnetic anisotropy ()-dependent AC magnetic softness including the Néel relaxation time constant(≈, effective relaxation time constant), and its dependent out-of-phase magnetic susceptibilityχ″primarily caused by the Cocation addition is the most dominant parameter to enhance the(SLP). This clarified result strongly suggests that the development of new design and synthesis methods enabling to significantly enhance theby improving the crystalline anisotropy, shape anisotropy, stress (magnetoelastic) anisotropy, thermally-induced anisotropy, and exchange anisotropy is the most critical to enhance the(SLP) of SPIONPs at the(particularly at the lower< 120 kHz) for clinically safe magnetic nanoparticle hyperthermia.