WannSymm: A symmetry analysis code for Wannier orbitals

We derived explicit expressions of symmetry operators on Wannier basis, and implemented these operators in WannSymm software. Based on this implementation, WannSymm can i) symmetrize the real-space Hamiltonian output from Wannier90 code, ii) generate symmetry operators of the little group at a specific k-point, and iii) perform symmetry analysis for Wannier band structure. In general, symmetrized Hamiltonians yield improved results compared with the original ones when they are employed for nodal structure searching, surface Green's function calculations, and other model calculations.

本团队推导出在 Wannier 基底上对称算符的显式表达式，并在 WannSymm 软件 中实现了这些算符。基于此实现，WannSymm 能够实现以下功能：i) 对由 Wannier90 代码输出的实空间哈密顿量进行对称化处理；ii) 在特定的 k 点生成小群的对称算符；iii) 对 Wannier 能带结构进行对称性分析。通常，当对称化后的哈密顿量被用于寻找节点结构、表面格林函数的计算以及其他模型计算时，相较于原始哈密顿量，其结果更为优异。