Dynamics of a Hole in the Large-U Hubbard Model: A Feynman Diagram Approach
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چکیده
We study trie dynamics of a single hole in an otherwise half-filled two-dimensional Hubbard model by introducing a nonlocal Bogolyubov transformation in trie antiferromagnetic state. This allows us to rewrite trie Hamiltonian in a form that makes a separation between highenergy processes (involving double-occupancy) and low-energy puysics possible. A diagrammatic scheme is developed tuat allows for a systematic study of trie dilferent processes delocalizing a carrier in the antiferromagnetic state. In particular, the so-called Trugman
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تاریخ انتشار 2016