Change of longitudinal spin Seebeck voltage with annealing in Y3Fe5O12 films formed by densely packed nanocrystals

• Published in: Journal of magnetism and magnetic materials 2021-10, Vol.535, p.168093, Article 168093
• Main Authors: Yamada, Keisuke, Masaki, Shinya, Yamamoto, Mikiya, Kondo, Keita, Kurokawa, Yuichiro, Shiota, Yoichi, Moriyama, Takahiro, Ono, Teruo, Yuasa, Hiromi, Shima, Mutsuhiro
• Format: Article
• Language: English
• Subjects: Annealing; Co-precipitation; Electric potential; Magnon; Magnons; Microstructure; Nanocrystals; Silicon substrates; Spin seebeck; Voltage; Y3Fe5O12
• ISSN: 0304-8853; 1873-4766
• DOI: 10.1016/j.jmmm.2021.168093

•Fabricated YIG films with densely packed nanocrystal on a Si substrate.•Decrease of LSSE voltage in YIG films with increasing annealing temperature and time.•Microstructural changes in YIG films by annealing cause the changes LSSE voltage.•Reduced coherence of the magnons is attributed to the decreased LSSE voltage. The changes of longitudinal spin Seebeck (LSSE) voltage with annealing temperature Ta and time in Y3Fe5O12 (YIG) films formed by densely packed nanocrystals on a Si substrate have been investigate. The value of thermoelectric performance (TP) decreases monotonically with increasing Ta from 1073 K to 1273 K, and it decreases by up to 24% (64%) in the YIG films with Pt = 5 nm (10 nm). The decreased TP is also observed with increasing annealing time. These results indicate that the microstructural changes in the YIG films by annealing temperature and time are caused the decreased TP, which are corresponded with a reduced coherence of the magnons in the YIG films.