一些关于厄米算符的结论至非厄米情形的扩展SOME CONCLUSIONS ABOUT HERMITIAN OPERATORS EXTENDED TO NON-HERMITIAN CASES
娄欣岚,徐大智,吴宁
摘要(Abstract):
本文将量子力学中关于厄米算符的一些熟知结论推广至非厄米算符情形。具体地,(1)给出了满足代数方程的非厄米算符的本征值结构;(2)针对一类可对角化的非厄米算符,阐明了对易性、简并子空间,以及块对角化之间的关系,给出了其可视化的图像;(3)以四格点自旋-1/2海森堡XXZ链为例具体说明了这些扩展结果的物理内涵和应用。
关键词(KeyWords): 非厄米算符;对易性;简并;共同本征态;块对角化
基金项目(Foundation): 科技部科技创新2030重大项目(2023ZD0300703);; 北京理工大学物理学院教改项目“科研成果融入本科量子力学教学”
作者(Author): 娄欣岚,徐大智,吴宁
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- (1)本例中的F为晶格动量算符,可通过将自旋链费米子化后在费米子模型的动量空间中写出,但这超出了本文的讨论范围。