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Title: Magnetic properties and spin reorientation of hexagonal HoFeO3 thin films
We present structural, magnetic, and optical properties of hexagonal HoFeO3/Al2O3 thin films deposited by Magnetron Sputtering. The x-ray diffraction patterns of HoFeO3 thin films show the c-planes of a hexagonal structure. The magnetization data display an antiferromagnetic transition temperature, TN∼120 ± 5 K and the magnetization-field hysteresis loops were measured below 100 K, confirming a weak ferromagnetism arising from a spin canting of the Fe3+ moments. The magnetization data also show an anomaly around ∼40 K due to a spin-reorientation transition caused by the Ho3+- Fe3+ interactions. We observed comparable magnetization along the ab plane and c axis although the spin canting of Fe3+ sites has a preferential component along the c axis, suggesting that the Ho3+- Fe3+ interactions dominate in the low temperature magnetic structures of hexagonal-HoFeO3. The observed electronic excitations at ∼2.29, 2.87, 3.82, 4.79, and 6.53 eV have been assigned to the Fe3+ d to d on-site as well as O 2p to Fe 3d, Ho 6s, and 5d charge-transfer excitations, respectively. The room temperature energy band gap of the hexagonal-HoFeO3 thin film was measured to be ∼1.99 ± 0.04 eV.
Authors:
Award ID(s):
1406766
Publication Date:
NSF-PAR ID:
10215735
Journal Name:
Thin solid films
Volume:
723
Page Range or eLocation-ID:
138596
ISSN:
0040-6090
Sponsoring Org:
National Science Foundation
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