Random phase approximation for the 1D anti-ferromagnetic Heisenberg model

A. Rabhi; P. Schuck; J. Da Providencia

doi:10.1088/0953-8984/18/45/011

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Random phase approximation for the 1D anti-ferromagnetic Heisenberg model

A. Rabhi·P. Schuck·J. Da Providencia

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Abstract

The Hartree-Fock-RPA approach is applied to the 1D anti-ferromagnetic Heisenberg model in the Jordan-Wigner representation. Somewhat contrary to expectation, this leads to reasonable results for spectral functions and sum rules in the symmetry unbroken phase. In a preliminary application of Self-Consistent RPA to finite size chains strongly improved results are obtained.

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A. Rabhi, P. Schuck, J. Da Providencia. 2007-01-24. Random phase approximation for the 1D anti-ferromagnetic Heisenberg model. https://doi.org/10.1088/0953-8984%2F18%2F45%2F011

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