Delta-Davidson method for interior eigenproblem in many-spin systems
Delta-Davidson method for interior eigenproblem in many-spin systems
复制标题
多自旋系统内部本征问题的 Delta-Davidson 方法
DOI：
10.1088/1674-1056/abd74a
复制
发表时间：
2021
影响因子：
1.7
通讯作者：
Zhang Wenxian
中科院分区：
文献类型：
--
作者：
Guan Haoyu;Zhang Wenxian
Many numerical methods, such as tensor network approaches including density matrix renormalization group calculations, have been developed to calculate the extreme/ground states of quantum many-body systems. However, little attention has been paid to the central states, which are exponentially close to each other in terms of system size. We propose a delta-Davidson (DELDAV) method to efficiently find such interior (including the central) states in many-spin systems. The DELDAV method utilizes a delta filter in Chebyshev polynomial expansion combined with subspace diagonalization to overcome the nearly degenerate problem. Numerical experiments on Ising spin chain and spin glass shards show the correctness, efficiency, and robustness of the proposed method in finding the interior states as well as the ground states. The sought interior states may be employed to identify many-body localization phase, quantum chaos, and extremely long-time dynamical structure.(paper)
