Nanoscale magnetism control via surface and exchange anisotropy for optimized ferrimagnetic hysteresis
Seung-hyun Noh ; Wonjun Na ; Jinwoo Cheon ; Jeon-Soo Shin ; Yongjun Lim ; Seung Ho Moon ; Eun Jung Lee ; Jae-Hyun Lee ; Jung-tak Jang
Nano Letters, Vol.12(7) : 3716~3721, 2012
With the aim of controlling nanoscale magnetism, we demonstrate an approach encompassing concepts of surface and exchange anisotropy while reflecting size, shape, and structural hybridization of nanoparticles. We visualize that cube has higher magnetization value than sphere with highest coercivity at 60 nm. Its hybridization into core-shell (CS) structure brings about a 14-fold increase in the coercivity with an exceptional energy conversion of magnetic field into thermal energy of 10600 W/g, the largest reported to date. Such capability of the CS-cube is highly effective for drug resistant cancer cell treatment.