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Title: Magnetism and microstructure of co-deposited yttrium iron garnet-barium titanate films
Yttrium iron garnet (YIG) and barium titanate (BTO) were co-deposited on (001)-orientated gadolinium gallium garnet substrates by pulsed laser deposition with composition determined by the ratio of laser shots ablating each target. With increasing shot ratios of YIG/BTO = 2.5/1, 4/1, 20/1, and 30/1, the majority phase in the film changes from textured polycrystalline perovskite to epitaxial garnet. Cross-sectional STEM characterization of the YIG-rich films reveals three distinct sublayers: the bottom layer is a coherent epitaxial garnet layer with higher unit cell volume than that of YIG; the second layer is garnet exhibiting crystalline defects and misorientation; and the upper layer is amorphous. Highly defective regions within the second layer are richer in Ba, suggesting that the microstructure is promoted by the insolubility of Ba in YIG. Temperature-dependent magnetization measurements fitted to a super-exchange dilution model indicate the presence of nonmagnetic Ti and vacancies in both octahedral and tetrahedral sites.  more » « less
Award ID(s):
1911792
PAR ID:
10423182
Author(s) / Creator(s):
;
Date Published:
Journal Name:
Applied Physics Letters
Volume:
121
Issue:
23
ISSN:
0003-6951
Page Range / eLocation ID:
231604
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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