Third-Order Elastic Constants in a Critical Region of Temperature

临界温度区的三阶弹性常数

• 批准号: 06640436
• 负责人: YAMAMOTO Ikuo
• 金额: $ 1.28万
• 依托单位: YOKOHAMA NATIONAL UNIVERSITY
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for General Scientific Research (C)
• 财政年份: 1994
• 资助国家: 日本
• 起止时间: 1994 至 1995
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-06640436/
• 关键词: Elastic Constant; Phase Transition; Stress Effect; Nonlinearity; Perovskite

Single crystals of perovskite-type crystal CsPbCl_3 were grown by the modified Stockbarger method. Two cubic samples of about 1 cm^3 were obtained in the present study. Ultrasonic wave velocities of CsPbCl_3 have been measured above the cubic-tetragonal phase trnsition temperature under hydrostatic pressure by the pulse-echo overlap method. Ultrasonic waves of the longitudinal or the transverse mode were generated by quartz transducers of fundamental frequency of 10 MHz.The combinations of third-order elastic constants C_<111>+2C_<112>'C_<111>-C_<123> and C_<144>+2C_<166> were deduced from pressure derivatives of the sound velocity over the temperature interval 47-100ﾟC.Critical anomalies were found in the temperature dependence of C_<111>+2C_<112> and C_<111>-C_<123>. It has been revealed that the order-parameter fluctuation is responsible for the observed anomaly in the third-order elastic constants .

采用改进的 Stockbarger 方法生长了钙钛矿型晶体 CsPbCl_3 的单晶，在静水压条件下测量了 CsPbCl_3 的超声波速度高于立方四方相转变温度。脉冲回波重叠法的压力由基本频率为 的石英换能器产生纵向或横向模式的超声波。 10 MHz。三阶弹性常数 C_<111>+2C_<112>'C_<111>-C_<123> 和 C_<144>+2C_<166> 的组合由声速的压力导数推导出来温度区间为 47-100°C。在温度依赖性中发现了关键异常C_<111>+2C_<112> 和 C_<111>-C_<123> 已表明，有序参数涨落是造成所观察到的三阶弹性常数异常的原因。

项目成果

白崎良演: "Effects of the Lattice Discretness on a Soliton" Jounal of the Physical Society of Japan. 1996 (65)

Yoshi Shirasaki：“格子离散性对孤子的影响”日本物理学会杂志 1996 (65)。

白崎良演: "Effects of the Lattice Discretmess on a Soliton" Jounal of the Physical Society of Japan. 65. (1996)

Yoshi Shirasaki：“晶格离散对孤子的影响”，日本物理学会杂志 65。（1996）

Ryoen SHIRASAKI: "Isotope Effect on Formation Energy of Soliton in t-Polyacetylene" Synthetic Metals. Vol.69. 677-678 (1995)

Ryoen Shirasaki：“同位素对叔聚乙炔中孤子形成能的影响”合成金属。

Ikuo YAMAMOTO: "Brillouin Scattering Study of the Volume Phase Transition in Poly-N-Isopropylacrylamide Gels" J.Phys.Soc.Jpn.Vol.64. 2898-2907 (1995)

Ikuo YAMAMOTO：“聚-N-异丙基丙烯酰胺凝胶中体积相变的布里渊散射研究”J.Phys.Soc.Jpn.Vol.64。

山本郁夫 他: "Brillouin Scattering Study of the Volume Transition in NIPA." Jounal of the Physical Society of Japan. 64. 2898-2907 (1995)

Ikuo Yamamoto 等人：“NIPA 中体积转变的布里渊散射研究”。日本物理学会杂志 64。2898-2907 (1995)