TY  - JOUR
AU  - Chen, Xinfeng
AU  - Higashikozono, Soma
AU  - Ito, Keita
AU  - Jin, Lei
AU  - Ho, Ping-Luen
AU  - Yu, Chu-Ping
AU  - Tai, Nyan-Hwa
AU  - Mayer, Joachim
AU  - Dunin-Borkowski, Rafal E.
AU  - Suemasu, Takashi
AU  - Zhong, Xiaoyan
TI  - Nanoscale measurement of giant saturation magnetization in α″-Fe16N2 by electron energy-loss magnetic chiral dichroism
JO  - Ultramicroscopy
VL  - 203
SN  - 0304-3991
CY  - Amsterdam
PB  - Elsevier Science
M1  - FZJ-2020-02975
SP  - 37 - 43
PY  - 2019
AB  - Metastable α″-Fe16N2 thin films were reported to have a giant saturation magnetization of above 2200 emu/cm3 in 1972 and have been considered as candidates for next-generation rare-earth-free permanent magnetic materials. However, their magnetic properties have not been confirmed unequivocally. As a result of the limited spatial resolution of most magnetic characterization techniques, it is challenging to measure the saturation magnetization of the α″-Fe16N2 phase, as it is often mixed with the parent α′-Fe8N phase in thin films. Here, we use electron energy-loss magnetic chiral dichroism (EMCD), aberration-corrected transmission electron microscopy, X-ray diffraction and macroscopic magnetic measurements to study α″-Fe16N2 (containing ordered N atoms) and α′-Fe8N (containing disordered N atoms). The ratio of saturation magnetization in α″-Fe16N2 to that in α′-Fe8N is determined to be 1.31 ± 0.10 from quantitative EMCD measurements and dynamical diffraction calculations, confirming the giant saturation magnetization of α″-Fe16N2. Crystallographic information is also obtained about the two phases, which are mixed on the nanoscale.
LB  - PUB:(DE-HGF)16
C6  - pmid:30862364
UR  - <Go to ISI:>//WOS:000465021000005
DO  - DOI:10.1016/j.ultramic.2019.02.016
UR  - https://juser.fz-juelich.de/record/878654
ER  -