Precise Determination of Acoustical Physical Constants of LiNbO_3 and LiTaO_3 Single Crystals

LiNbO_3和LiTaO_3单晶声学物理常数的精确测定

基本信息

批准号：
07455127
负责人：
KUSHIBIKI Jun-ichi
金额：
$ 4.74万
依托单位：
Tohoku University
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (B)
财政年份：
1995
资助国家：
日本
起止时间：
1995 至 1996
项目状态：
已结题

来源：
https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-07455127/
关键词：
Acoustical physical constants New determination method Line-focus-beam acoustic microscopy bulk ultrasonic spectroscopy LiNbO_3 and LiTaO_3 Leaky surface acoustic wave velocity Bulk longitudinal shear velocity Density

项目摘要

In this study, we have developed a new method of determining the acoustical physical constants associated with piezoelectric crystals, using two systems of line-focus-beam acoustic microscopy and bulk ultrasonic spectroscopy, and have determined precisely all the independent constants of LiNbO_3 and LiTaO_3 single crystals, including the density.1. In order to improve reliability and reproducibility of the two systems, the measurement environment of temperature has been stabilized and a laser interferometer has been introduced to measure the absolute distance. Absolute accuracy of better than (]SY.+-。[)0.01% in velocity has been achieved.2. Many crystalline plane specimens of LiNbO_3 and LiTaO_3 with optically polished surfaces and excellent parallelism of front and back surfaces have been prepared from one ingot for each crystal.3. A new method of determining the acoustical physical constants, viz., stiffness, piezoelectric, and dielectric constants, has been developed using the two systems for velocity measurements.4. The acoustical physical constants of LiNbO_3 and LiTaO_3 have been determined, which provide five significant digits for bulk and surface acoustic wave velocities.5. The elastic constants for multi-domain LiTaO_3 crystals have been also determined, for the first time, and have been compared with those for single-domain LiTaO_3 crystals. It has been shown that the poling operation to introduce piezoelectricity is responsible for the differences of elastic properties between single-and multi-domain crystals.

在这项研究中，我们开发了一种确定与压电晶体相关的声学物理常数的新方法，使用线聚焦声束声学显微镜和体超声光谱学两个系统，并精确地确定了LiNbO_3和LiTaO_3单晶的所有独立常数。 1．为了提高两个系统的可靠性和再现性，稳定了温度的测量环境，并引入了激光干涉仪进行测量。绝对距离精度优于(]SY.+-.[)0.01%。 2．制备了许多表面经过光学抛光、前后表面平行度良好的LiNbO_3和LiTaO_3晶面样品。 3. 使用这两种速度系统开发了一种确定声学物理常数（即刚度、压电常数和介电常数）的新方法。 4. 确定了 LiNbO_3 和 LiTaO_3 的声学物理常数，为体声波和表面声波速度提供了 5 位有效数字。 5. 还首次确定了多域 LiTaO_3 晶体的弹性常数，并将其与单畴LiTaO_3晶体进行比较，结果表明引入压电性的极化操作是造成两者弹性性能差异的原因。单畴和多畴晶体。