Soft-phonon mode observation in Li 2Ge 4O 9 phase above room temperature

Yoshihiro Takahashi, Jun Kunitomo, Kensaku Nakamura, Minoru Osada, Takumi Fujiwara

Research output: Contribution to journalArticle

7 Citations (Scopus)

Abstract

Li 2Ge 4O 9 is known to be a ferroelectric phase with Curie temperature at T c ∼ -93 C. In this study, we found both the lowest-frequency phonon and heat-capacity anomalies around 100 C in the Li 2Ge 4O 9 phase, demonstrating their presence in the structural phase-transition. The phase transition is probably triggered by regularization of distorted GeO 6 octahedra in the paraelectric phase, resulting in another phase consisting of the regular octahedral GeO 6 unit, which was supported by in situ measurement of emission of 2E → 4A 2 transition in the Mn 4-doped phase. It is deduced that the phase transition is more dynamic than ferroelectric phase-transition originating in ordering of the Li ions.

Original languageEnglish
Article number091902
JournalApplied Physics Letters
Volume100
Issue number9
DOIs
Publication statusPublished - 2012 Feb 27
Externally publishedYes

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room temperature
in situ measurement
Curie temperature
specific heat
anomalies
low frequencies
ions

ASJC Scopus subject areas

  • Physics and Astronomy (miscellaneous)

Cite this

Takahashi, Y., Kunitomo, J., Nakamura, K., Osada, M., & Fujiwara, T. (2012). Soft-phonon mode observation in Li 2Ge 4O 9 phase above room temperature. Applied Physics Letters, 100(9), [091902]. https://doi.org/10.1063/1.3688603

Soft-phonon mode observation in Li 2Ge 4O 9 phase above room temperature. / Takahashi, Yoshihiro; Kunitomo, Jun; Nakamura, Kensaku; Osada, Minoru; Fujiwara, Takumi.

In: Applied Physics Letters, Vol. 100, No. 9, 091902, 27.02.2012.

Research output: Contribution to journalArticle

Takahashi, Y, Kunitomo, J, Nakamura, K, Osada, M & Fujiwara, T 2012, 'Soft-phonon mode observation in Li 2Ge 4O 9 phase above room temperature', Applied Physics Letters, vol. 100, no. 9, 091902. https://doi.org/10.1063/1.3688603
Takahashi Y, Kunitomo J, Nakamura K, Osada M, Fujiwara T. Soft-phonon mode observation in Li 2Ge 4O 9 phase above room temperature. Applied Physics Letters. 2012 Feb 27;100(9). 091902. https://doi.org/10.1063/1.3688603
Takahashi, Yoshihiro ; Kunitomo, Jun ; Nakamura, Kensaku ; Osada, Minoru ; Fujiwara, Takumi. / Soft-phonon mode observation in Li 2Ge 4O 9 phase above room temperature. In: Applied Physics Letters. 2012 ; Vol. 100, No. 9.
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