Quasiharmonic model for ferroelectric transition in 18O-isotope exchanged SrTiO3
Quasiharmonic model for ferroelectric transition in 18O-isotope exchanged SrTiO3
复制标题
18O-同位素交换 SrTiO3 中铁电转变的准谐波模型
DOI:
10.1088/0953-8984/20/5/055223
复制
发表时间:
2008
期刊:
影响因子:
--
通讯作者:
H. Mashiyama
中科院分区:
文献类型:
--
作者:
S. E. Mkam Tchouobiap;H. Mashiyama
By extending the quasiharmonic approximation to a quantum particle within a local potential of the double Morse type, a model describing the ferroelectric phase transition in SrTiO3 induced by oxygen isotope replacement is developed. The theory uses the variational principle method at finite temperature with emphasis on the quantum effect manifested in zero-point vibration. The ferroelectric–paraelectric transition in SrTi(16O1−x18Ox)3 is analyzed and the x–Tc phase diagram is compared with the experimental one in order to confirm the qualitative validity of the model. The quantum mechanical effect and the evolution of the ferroelectricity in SrTi(16O1−x18Ox)3 are also demonstrated theoretically and the soft mode of SrTi(16O1−x18Ox)3 shows a perfect softening at the ferroelectric phase transition for x≥xc≈0.32. Finally, the study shows the importance of the mass of component ions and that isotope introduction has several effects even if the mass effect is predominant.
DOI:
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发表时间:
2005
期刊:
J.Phys.Soc.Jpn. 74 Suppl.
影响因子:
--
作者:
N.Maeshima et al.
通讯作者:
N.Maeshima et al.
DOI:
--
发表时间:
2006
期刊:
Phys. Rev. Lett. 96
影响因子:
--
作者:
M. Takesada;M. Itoh;A. Onodera;and T. Yagi;Masaki TAKESADA;Tadahiko ISHIKAWA;Seiko MOURI;Masaki TAKESADA;Hiroki TANIGUCHI;Masaki TAKESADA
通讯作者:
Masaki TAKESADA