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作者单位:S. M. Tashpulatov (1)
1. Institute for Nuclear Physics, Academy of Sciences of the Republic of Uzbekistan, Tashkent, Uzbekistan
ISSN:1573-9333
文摘
We investigate spectral properties of a three-electron system in the Hubbard model framework. We prove that the essential spectrum of the system in a quartet state consists of a single segment and the three-electron bound state is absent. We show that the essential spectrum of the system in doublet states is the union of at most three segments. We also prove that three-electron bound states exist in doublet states.