Achieving a high cutting-off frequency in the oriented CoFe2O4 nanocubes.

Authors :: Ningning Song
Shangzhi Gu
Jun Zhou
Weixing Xia
Panpan Zhang
Qeemat Gul
Wei Wang
Haitao Yang
Zhaohua Cheng
Source :: Applied Physics Letters; 9/25/2017, Vol. 111 Issue 13, p133108-1-133108-4, 4p, 1 Black and White Photograph, 1 Illustration, 2 Graphs
Publication Year :: 2017
Abstract: An effective way for the improvement of resonance frequency was demonstrated by the orientation of CoFe<subscript>2</subscript>O<subscript>4</subscript> nanocubes (NCs) after applying a magnetic field. The magnetic holography image of the oriented CoF<subscript>2</subscript>O<subscript>4</subscript> NC arrays was obtained, and the vortex domain structure was found in single CoFe<subscript>2</subscript>O<subscript>4</subscript> NCs, which greatly depends on dipolar interactions. Moreover, the cutting-off frequency of oriented CoFe<subscript>2</subscript>O<subscript>4</subscript> NCs of 8.8 GHz is achieved with a slight increase in permeability at an extremely low mass fraction (about 10%). This work provides an effective way for optimizing the high-frequency properties of magnetic nanomaterials above GHz. [ABSTRACT FROM AUTHOR]