Doping induced spinless collective excitations of charge 2e in doped Mott insulators

W. Vincent Liu

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Doping induced spinless collective excitations of charge 2e in doped Mott insulators

W. Vincent Liu

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Abstract

Based on the Hubbard model description of the doped Mott insulator, we prove that there must exist a spinless collective excitation of charge $2e$ and of energy $U-2μ$ peaked at momentum $(π/a,π/a)$ in the non-superconducting state due to doping. Such a collective excitation arises from the electron pair correlation. Its existence is related to the breakdown of an approximate SU(2) particle-hole symmetry, from which an effective field theory of the new excitations is constructed.

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W. Vincent Liu. 2000-10-29. Doping induced spinless collective excitations of charge 2e in doped Mott insulators. https://arxiv.org/abs/cond-mat/0010470

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