...
  • 主题
高级搜索  >
历史搜索 清空历史
首页> 外文期刊>Physica, A. Statistical mechanics and its applications >Mean-field study of the degenerate Blume-Emery-Griffiths model in a random crystal field
【24h】

Mean-field study of the degenerate Blume-Emery-Griffiths model in a random crystal field

机译：随机晶场中退化Blume-Emery-Griffiths模型的平均场研究

获取原文
获取原文并翻译 | 示例
           
页面导航
  • 摘要
  • 著录项
  • 相似文献
  • 相关主题

摘要

The degenerate Blume-Emery-Griffiths (DBEG) model has recently been introduced in the study of martensitic transformation problems. This model has the same Hamiltonian as the standard Blume-Emery-Griffiths (BEG) model but, to take into account vibrational effects on the martensitic transition, it is assumed that the states S = 0 have a degeneracy p (p = 1 corresponds to the usual BEG model). This model was studied by E. Vives et al. for a particular value of Delta, through a mean-field approximation and numerical simulation. When the parameter p increases, the ferromagnetic phase shrinks and the region where the transition is of first order increases. In some materials, however, the transition would be better described by a disordered DBEG model; further, the inclusion of disorder in the DBEG model may be relevant in the study of shape memory alloys. From the theoretical point of view, it would be interesting to study the consequence of conflicting effects: the parameter p, which increases the first-order phase-transition region, and disorder in the crystal field, which tends to diminish this region in three dimensions. In order to study this competition in high-dimensional systems, we apply a mean-held approximation: it is then possible to determine the critical behavior of the random DBEG model for any value of the interaction parameters. Finally, we comment on (preliminary) results obtained for a two-dimensional system, where the randomness in the crystal field has a more drastic effect, when compared to the three-dimensional model. (C) 1998 Elsevier Science B.V. All nights reserved. [References: 8]
机译：退化的Blume-Emery-Griffiths（DBEG）模型最近已用于研究马氏体转变问题。该模型具有与标准Blume-Emery-Griffiths（BEG）模型相同的哈密顿量，但考虑到对马氏体转变的振动影响，假定状态S = 0的简并性为p（p = 1对应于通常的BEG模型）。该模型由E.Vives等人研究。通过均值场近似和数值模拟获得特定的Delta值。当参数p增加时，铁磁相收缩并且一阶跃迁的区域增加。但是，在某些材料中，可以通过无序的DBEG模型更好地描述过渡。此外，在形状记忆合金的研究中，DBEG模型中包含的无序可能是相关的。从理论的角度来看，研究冲突效应的结果将是有趣的：参数p增加了一阶相变区域，而晶体场的无序则倾向于在三个维度上减小该区域。为了研究高维系统中的竞争，我们应用均值近似法：然后可以确定任意参数的交互值的随机DBEG模型的临界行为。最后，我们对二维系统获得的（初步）结果进行了评论，与三维模型相比，该晶体系统中的晶体场随机性具有更大的影响。 （C）1998 Elsevier Science B.V.整夜保留。 [参考：8]

著录项

相似文献

  • 外文文献
  • 中文文献
  • 专利
获取原文

客服邮箱：kefu@zhangqiaokeyan.com

京公网安备：11010802029741号 ICP备案号：京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有

  • 客服微信

  • 服务号