Spin-glasslike behavior of magnetic ordered state originating from strong interparticle magnetostatic interaction in α-Fe nanoparticle agglomerate

Abstract

In strongly interacting nanoparticle agglomerate through dipolar coupling, prepared using chemically synthesized α-Fe nanoparticle, the temperature Tpeak at which the zero-field-cooled magnetization exhibits its peak reaches 385 K. This indicates that the magnetic ordering appears above room temperature. Aging phenomena and memory effect observed below Tpeak are intrinsically same as that of spin glasses. The appearance of spin-glasslike behavior near room temperature should be attributed to the three-dimensional interparticle coupling that is purely magnetostatic.