浅析电介质的极化——从物理竞赛题到几何相位  

BRIEF ANALYSIS OF THE POLARIZATION OF DIELECTRICS-FROM PHYSICS COMPETITION PROBLEMS TO GEOMETRIC PHASES

作　　者：陈曦 胡继超[1] CHEN Xi;HU Jichao(The High School affiliated to Renming University of China,Beijing 100080)

机构地区：[1]中国人民大学附属中学,北京100080

出　　处：《物理与工程》2024年第5期211-217,共7页Physics and Engineering

摘　　要：在电磁学和电动力学教学内容中,介质的极化是非常重要的组成部分。为了给学生们解释极化的微观机制,教材通常采用了洛伦兹模型的物理图像。该物理图像清晰简单,有利于初学者快速理解极化的物理本质。但洛伦兹模型却存在一定程度的不自洽性。此外,使用洛伦兹模型解决物理竞赛题时,也出现了悖论。本文中,我们首先回顾物理竞赛题目中的这个经典悖论,然后介绍了介质极化矢量更严格的定义,描述了介质极化过程中发生的微观物理过程,并在此基础上用热力学解释了悖论出现的原因和解决方法,最后简单介绍了计算介质极化的几何相位理论。In the syllabus of electromagnetism and electrodynamics,the polarization of the medium is a very important part.To explain the microscopic mechanism of polarization to students,textbooks often adopt the physical image of the Lorentz model.This physical image is clear and simple,which is helpful for beginners to quickly understand the physical nature of polarization.However,the Lorentz model has a certain degree of inconsistency.In addition,paradoxes arise when using the Lorentz model to solve physics competition problems.In this paper,we first review this classic paradox in the physics competition problems,and then introduce a more rigorous definition of the medium polarization vector,describe the microscopic physical processes that occur during the polarization of the medium,and on this basis,explain the reasons and solutions for the appearance of the paradox using thermodynamics.Finally,we briefly introduce the geometric phase theory for calculating the polarization of the medium.

关 键 词：极化 洛伦兹模型 极化能 热力学势 电致伸缩效应 几何相位 

分 类 号：O44[理学—电磁学]