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arXiv · 1708.07219

Role of small-norm components in extended random-phase approximation

Mitsuru Tohyama
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Abstract

The role of the small-norm amplitudes in extended RPA theories such as the particle-particle and hole-hole components of one-body amplitudes and the two-body amplitudes other than two particle - two holes components are investigated for the one-dimensional Hubbard model using an extended RPA derived from the time-dependent density-matrix theory. It is found that these amplitudes cannot be neglected in strongly interacting regions where the effects of ground-state correlations are significant.

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Mitsuru Tohyama. 2017-08-23. Role of small-norm components in extended random-phase approximation. https://arxiv.org/abs/1708.07219

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