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Dynamical density correlation function of 1D Mott insulators in a magnetic field

Davide Controzzi·Fabian H. L. Essler
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Abstract

We consider the one dimensional (1D) extended Hubbard model at half filling in the presence of a magnetic field. Using field theory techniques we calculate the dynamical density-density correlation function $χ_{nn}(ω,q)$ in the low-energy limit. When excitons are formed, a singularity appears in $χ_{nn}(ω,q)$ at a particular energy and momentum transfer.

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Davide Controzzi, Fabian H. L. Essler. 2002-04-28. Dynamical density correlation function of 1D Mott insulators in a magnetic field. https://doi.org/10.1103/physrevb.66.165112

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