3+1D哈密尔顿格子费米子的精确状对称性
Lei Gioia1,2, Ryan Thorngren3
1Caltech, Walter Burke Institute for Theoretical Physics, Pasadena, California, USA.
Physical review letters
|March 1, 2026
概括
我们开发了新的哈密尔顿模型,用于网格上的韦尔费米子,利用非局部对称性来保护奇拉性质. 这些模型为拓阶段提供了新的见解,避免了理论限制.
科学领域:
- 凝聚物质物理学 凝聚物质物理学
- 高能物理 高能物理
- 量子场理论 量子场理论
背景情况:
- 韦尔费米子是具有独特奇拉性质的基本粒子.
- 格子模型对于研究量子场理论和拓阶段至关重要.
- 螺旋对称和异常在粒子物理学和凝聚物质现象中起着关键作用.
研究的目的:
- 为单个韦尔费米子和韦尔双子构建哈密尔顿格子模型.
- 为了研究精确的奇拉对称性在保护费米子无间隙的作用.
- 探索新的对称性及其对拓相和异常的影响.
主要方法:
- 在3+1D立方格子上构建哈密尔顿模型.
- 使用非现场对称度,包括非紧的合和U{1}对称度.
- 在紫外线中分析出现的SU(2) 味道对称性和Onsager代数.
- 对2+1D中的迪拉克的U(1) T平价异常的调查.
主要成果:
- 一个汉密尔顿对应的金斯帕格-威尔逊对称的单个韦尔费米子.
- 一个磁性韦尔半金属模型,具有两个精确的U(1) 对称性,保护全球SU(2) 异常.
- 即使在晶体转换被打破时,也可以证明缺口保护.
- 在2+1D中构建一个以对称性保护的迪拉克,具有U(1) T平价异常.
结论:
- 新的格子构造通过使用非现场对称度来规避现有的不行定理.
- 这些模型为研究具有精确合对称性的拓相提供了一个框架.
- 这些发现提供了对异常及其在保护无差距国家中的作用的新视角.
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