Films of polycrystalline terbium iron garnet (TbIG), cerium‐substituted TbIG (CeTbIG), and bismuth‐substituted TbIG (BiTbIG) are grown on Si substrates by pulsed laser deposition. The films grow under tensile strain due to thermal mismatch with the Si substrate, resulting in a dominant magnetoelastic anisotropy which, combined with shape anisotropy, leads to in‐plane magnetization. TbIG has a compensation temperature of 253 K which is reduced by substitution of Ce and Bi. The Faraday rotation at 1550 nm of the TbIG, Ce0.36TbIG, and Bi0.03TbIG films is 5400 ± 600° cm−1, 4500 ± 100° cm–1, and 6200 ± 300° cm−1, respectively, while Ce0.36TbIG and Bi0.03TbIG exhibit lower optical absorption than TbIG, attributed to a reduction in Fe2+and Tb4+absorption pathways. The high Faraday rotation of the films, and in particular the high magneto‐optical figure of merit of the Bi0.03TbIG of 720° dB−1at 1550 nm, make these polycrystalline films valuable for applications in integrated photonics.
- Award ID(s):
- 2122041
- NSF-PAR ID:
- 10421810
- Date Published:
- Journal Name:
- Magnetochemistry
- Volume:
- 9
- Issue:
- 1
- ISSN:
- 2312-7481
- Page Range / eLocation ID:
- 25
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.3390/magnetochemistry9010025
