New Types of Structural Phase Transition and The Dynamics

新型结构相变及其动力学

基本信息

批准号：
60302023
负责人：
HORIE Chuji
金额：
$ 3.26万
依托单位：
TOHOKU UNIVERSITY
依托单位国家：
日本
项目类别：
Grant-in-Aid for Co-operative Research (A)
财政年份：
1985
资助国家：
日本
起止时间：
1985 至 1986
项目状态：
已结题

来源：
https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-60302023/
关键词：
structural phase transition charge density wave (CDW)commensurate-incommensurate transition soliton discommensuration formation and growth of pattern glass transition ステージ転移

项目摘要

Results of the research are summarized as follows:1. Photo-induced structural phase transition: This is a new type of transition between non-equilibrium systems. The new idear and interpretation was obtained for concrete examples.2. Charge density waves (CDW) : The commensurate and incommensurate (C-IC) transition accompanying CDW was studied both macro- and microscopic points of view. The important roles of electron-lattice interactions was ellucidated.3. Dynamics of C-IC transitions, formation and growth of patterns: It eas pointed out that the transition process is described in terms of motion of discommensurations.4. Dynamics of solitons: The fundamental relation between fluctuations and pinning od CDW and superconducting state was made clear. The effect of collision of solitons with phonons was investigated.5. Glass transition: A new technique for molecular dynamics under isothermal or isobaric conditions was developed and applied to investigate the annealing effect. It was shown that there was a possibility for finding a new type of glass phase in the system composed of ferro-electric and antiferro-electric materials.6. Stage transformation in intercalation compounds: Temporal development of stage transformation in graphite intercalation compounds was investigated by means of computer simulation.7. Others: The microscopic mechanism of premartensitic transformation was proposed.

研究结果如下： 1．光诱导结构相变：这是非平衡系统之间的一种新型转变。通过具体实例得到了新的思路和解释。 2．电荷密度波 (CDW)：从宏观和微观角度研究了伴随 CDW 的等量和不等量 (C-IC) 转变。阐明了电子-晶格相互作用的重要作用。 3． C-IC转变的动力学、模式的形成和增长：很容易指出，转变过程是用不通约运动来描述的。 4．孤子动力学：阐明了CDW的涨落和钉扎与超导态之间的基本关系。研究了孤子与声子碰撞的影响。 5．玻璃化转变：开发了一种等温或等压条件下分子动力学的新技术，并应用于研究退火效应。结果表明，在铁电和反铁电材料组成的体系中，有可能找到一种新型玻璃相。 6．层间化合物的阶段转变：通过计算机模拟研究了石墨层间化合物阶段转变的时间发展。 7．其他：提出了预马氏体相变的微观机制。