带矩阵的流方程
Flow equations for band--matrices
摘要：
连续酉变换可以用来对角化或近似对角化给定的哈密顿量。在过去的四年中，这种方法已被应用于各种模型的凝聚态物理和场论。本文提出了一种新的连续酉变换生成元，它可以避免以往应用中的一些问题。新的生成器的一般性质推导。事实证明，新的生成器是特别有用的哈密顿与带状结构。两个例子，Lipkin模型，自旋玻色子模型进行了详细讨论。
英文摘要：
Continuous unitary transformations can be used to diagonalize or approximately diagonalize a given Hamiltonian. In the last four years, this method has been applied to a variety of models of condensed matter physics and field theory. With a new generator for the continuous unitary transformation proposed in this paper one can avoid some of the problems of former applications. General properties of the new generator are derived. It turns out that the new generator is especially useful for Hamiltonians with a banded structure. Two examples, the Lipkin model, and the spin--boson model are discussed in detail.
机构、总结、中文摘要均由AI分析而来，可能存在错误，请以论文正文为准。
