start-ver=1.4 cd-journal=joma no-vol=126 cd-vols= no-issue=1 article-no= start-page=012901 end-page= dt-received= dt-revised= dt-accepted= dt-pub-year=2025 dt-pub=20250102 dt-online= en-article= kn-article= en-subject= kn-subject= en-title= kn-title=Dynamic domain motion enhancing electro-optic performance in ferroelectric films en-subtitle= kn-subtitle= en-abstract= kn-abstract=With the rapid advancement of information technology, there is a pressing need to develop ultracompact and energy-efficient thin-film-based electro-optic (EO) devices. A high EO coefficient in ferroelectric materials is crucial. However, substrate clamping can positively or negatively influence various physical properties, including the EO response of these films, thus complicating the development of next-generation thin-film-based devices. This study demonstrates that reversible dynamic domain motion, achieved through substrate clamping, significantly enhances the EO coefficient in epitaxial ferroelectric rhombohedral Pb(Zr, Ti)O3 thin films, where the (111) and (⁠ 111⁠) domains coexist with distinct optical axes. In principle, this approach can be applied to different film-substrate systems, thereby contributing to the advancement of sophisticated EO devices based on ferroelectrics. en-copyright= kn-copyright= en-aut-name=KondoShinya en-aut-sei=Kondo en-aut-mei=Shinya kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=1 ORCID= en-aut-name=OkamotoKazuki en-aut-sei=Okamoto en-aut-mei=Kazuki kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=2 ORCID= en-aut-name=SakataOsami en-aut-sei=Sakata en-aut-mei=Osami kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=3 ORCID= en-aut-name=TeranishiTakashi en-aut-sei=Teranishi en-aut-mei=Takashi kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=4 ORCID= en-aut-name=KishimotoAkira en-aut-sei=Kishimoto en-aut-mei=Akira kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=5 ORCID= en-aut-name=NagasakiTakanori en-aut-sei=Nagasaki en-aut-mei=Takanori kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=6 ORCID= en-aut-name=YamadaTomoaki en-aut-sei=Yamada en-aut-mei=Tomoaki kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=7 ORCID= affil-num=1 en-affil=Graduate School of Environmental, Life, Natural Science and Technology, Okayama University kn-affil= affil-num=2 en-affil=Department of Energy Engineering, Nagoya University kn-affil= affil-num=3 en-affil=Japan Synchrotron Radiation Research Institute (JASRI) kn-affil= affil-num=4 en-affil=Graduate School of Environmental, Life, Natural Science and Technology, Okayama University kn-affil= affil-num=5 en-affil=Graduate School of Environmental, Life, Natural Science and Technology, Okayama University kn-affil= affil-num=6 en-affil=Department of Energy Engineering, Nagoya University kn-affil= affil-num=7 en-affil=Department of Energy Engineering, Nagoya University kn-affil= END start-ver=1.4 cd-journal=joma no-vol=14 cd-vols= no-issue=20 article-no= start-page=1677 end-page= dt-received= dt-revised= dt-accepted= dt-pub-year=2024 dt-pub=20241018 dt-online= en-article= kn-article= en-subject= kn-subject= en-title= kn-title=Colossal Dielectric Constant of Nanocrystalline/Amorphous Homo-Composite BaTiO3 Films Deposited via Pulsed Laser Deposition Technique en-subtitle= kn-subtitle= en-abstract= kn-abstract=We report the pulsed laser deposition (PLD) of nanocrystalline/amorphous homo-composite BaTiO3 (BTO) films exhibiting an unprecedented combination of a colossal dielectric constant (epsilon(r)) and extremely low dielectric loss (tan delta). By varying the substrate deposition temperature (T-d) over a wide range (300-800 degrees C), we identified T-d = 550 degrees C as the optimal temperature for growing BTO films with an epsilon(r) as high as similar to 3060 and a tan delta as low as 0.04 (at 20 kHz). High-resolution transmission electron microscopy revealed that the PLD-BTO films consist of BTO nanocrystals (similar to 20-30 nm size) embedded within an otherwise amorphous BTO matrix. The impressive dielectric behavior is attributed to the combination of highly crystallized small BTO nanograins, which amplify interfacial polarization, and the surrounding amorphous matrix, which effectively isolates the nanograins from charge carrier transport. Our findings could facilitate the development of next-generation integrated dielectric devices. en-copyright= kn-copyright= en-aut-name=KondoShinya en-aut-sei=Kondo en-aut-mei=Shinya kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=1 ORCID= en-aut-name=MurakamiTaichi en-aut-sei=Murakami en-aut-mei=Taichi kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=2 ORCID= en-aut-name=PichonLoick en-aut-sei=Pichon en-aut-mei=Loick kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=3 ORCID= en-aut-name=Leblanc-LavoieJoel en-aut-sei=Leblanc-Lavoie en-aut-mei=Joel kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=4 ORCID= en-aut-name=TeranishiTakashi en-aut-sei=Teranishi en-aut-mei=Takashi kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=5 ORCID= en-aut-name=KishimotoAkira en-aut-sei=Kishimoto en-aut-mei=Akira kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=6 ORCID= en-aut-name=El KhakaniKhakani, My Ali en-aut-sei=El Khakani en-aut-mei=Khakani, My Ali kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=7 ORCID= affil-num=1 en-affil=Graduate School of Environmental, Life, Natural Science and Technology, Okayama University kn-affil= affil-num=2 en-affil=Graduate School of Environmental, Life, Natural Science and Technology, Okayama University kn-affil= affil-num=3 en-affil=Institut National de la Recherche Scientifique (INRS), Centre Énergie, Matériaux et Télécommunications kn-affil= affil-num=4 en-affil=Institut National de la Recherche Scientifique (INRS), Centre Énergie, Matériaux et Télécommunications kn-affil= affil-num=5 en-affil=Graduate School of Environmental, Life, Natural Science and Technology, Okayama University kn-affil= affil-num=6 en-affil=Graduate School of Environmental, Life, Natural Science and Technology, Okayama University kn-affil= affil-num=7 en-affil=Institut National de la Recherche Scientifique (INRS), Centre Énergie, Matériaux et Télécommunications kn-affil= en-keyword=BaTiO3 kn-keyword=BaTiO3 en-keyword=thin film kn-keyword=thin film en-keyword=colossal dielectric constant kn-keyword=colossal dielectric constant en-keyword=nanocrystalline/amorphous homo-composite kn-keyword=nanocrystalline/amorphous homo-composite en-keyword=pulsed laser deposition kn-keyword=pulsed laser deposition END start-ver=1.4 cd-journal=joma no-vol=65 cd-vols= no-issue=14 article-no= start-page=2197 end-page=2200 dt-received= dt-revised= dt-accepted= dt-pub-year=2011 dt-pub=20110731 dt-online= en-article= kn-article= en-subject= kn-subject= en-title= kn-title=Effect of varying the ratio of matrix/dispersoid particle size on the piezoresistivity of alumina/carbon-black composite ceramics en-subtitle= kn-subtitle= en-abstract= kn-abstract=Alumina/carbon-black composite ceramics with different percolation thresholds were fabricated by changing the size ratio of constituent particles. The dependence of resistivity on pressure was established for each sample. The compositional dependence of resistivity can be explained by percolation theory. The percolation threshold decreases with increasing alumina/carbon-black particle size ratio. The pressure dependence of the resistivity increases as the composition approaches the percolation threshold. When the relative composition at the percolation threshold is fixed, the sensitivity increases with increasing matrix/dispersoid initial particle size ratio. en-copyright= kn-copyright= en-aut-name=KishimotoAkira en-aut-sei=Kishimoto en-aut-mei=Akira kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=1 ORCID= en-aut-name=TakagawaYuto en-aut-sei=Takagawa en-aut-mei=Yuto kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=2 ORCID= en-aut-name=TeranishiTakashi en-aut-sei=Teranishi en-aut-mei=Takashi kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=3 ORCID= en-aut-name=HayashiHidetaka en-aut-sei=Hayashi en-aut-mei=Hidetaka kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=4 ORCID= affil-num=1 en-affil= kn-affil=Division of Molecular and Material Science, Graduate School of Natural Science and Technology, Okayama University affil-num=2 en-affil= kn-affil=Division of Molecular and Material Science, Graduate School of Natural Science and Technology, Okayama University affil-num=3 en-affil= kn-affil=Division of Molecular and Material Science, Graduate School of Natural Science and Technology, Okayama University affil-num=4 en-affil= kn-affil=Division of Molecular and Material Science, Graduate School of Natural Science and Technology, Okayama University en-keyword=Percolation kn-keyword=Percolation en-keyword=Piezoresistivity kn-keyword=Piezoresistivity en-keyword=Pressure sensor kn-keyword=Pressure sensor en-keyword=Particle size kn-keyword=Particle size END start-ver=1.4 cd-journal=joma no-vol=34 cd-vols= no-issue=4 article-no= start-page=845 end-page=848 dt-received= dt-revised= dt-accepted= dt-pub-year=2008 dt-pub=200805 dt-online= en-article= kn-article= en-subject= kn-subject= en-title= kn-title=Improvement of piezoresistance properties of silicon carbide ceramics through co-doping of aluminum nitride and nitrogen en-subtitle= kn-subtitle= en-abstract= kn-abstract=The piezoresistance coefficient was measured on co-doped silicon carbide ceramics. Evaluation samples of alpha-silicon carbide ceramics were first fabricated by glass capsule HIP method using powder mixture of silicon carbide and aluminum nitride with various ratios. The resultant aluminum nitride added silicon carbide ceramics were doped with nitrogen by changing the post-HIP nitrogen gas pressure. The lattice parameter increased with the amount of adding aluminum nitride indicating that the incorporated aluminum substituted smaller silicon atoms. After post-HIP treatment, lattice parameter then decreased with nitrogen gas pressure. The piezoresistive coefficient increased with the addition of aluminum nitride, it further increased with the nitrogen doping pressure. en-copyright= kn-copyright= en-aut-name=KishimotoAkira en-aut-sei=Kishimoto en-aut-mei=Akira kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=1 ORCID= en-aut-name=OkadaYasuyuki en-aut-sei=Okada en-aut-mei=Yasuyuki kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=2 ORCID= en-aut-name=HayashiHidetaka en-aut-sei=Hayashi en-aut-mei=Hidetaka kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=3 ORCID= affil-num=1 en-affil= kn-affil=Division of Chemistry and Biochemistry, Graduate School of Natural Science and Technology, Okayama University affil-num=2 en-affil= kn-affil=Division of Chemistry and Biochemistry, Graduate School of Natural Science and Technology, Okayama University affil-num=3 en-affil= kn-affil=Division of Chemistry and Biochemistry, Graduate School of Natural Science and Technology, Okayama University en-keyword=HIP kn-keyword=HIP en-keyword=co-doping kn-keyword=co-doping en-keyword=donor kn-keyword=donor en-keyword=acceptor kn-keyword=acceptor en-keyword=silicon carbide kn-keyword=silicon carbide en-keyword=strain sensor kn-keyword=strain sensor END