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arXiv · 0809.3024

Spectral properties of a partially spin-polarized one-dimensional Hubbard/Luttinger superfluid

Adrian E. Feiguin·David A. Huse
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Abstract

We calculate the excitation spectra of a spin-polarized Hubbard chain away from half-filling, using a high-precision momentum-resolved time-dependent Density Matrix Renormalization Group method. Focusing on the U<0 case, we present in some detail the single-fermion, pair, density and spin spectra, and discuss how spin-charge separation is altered for this system. The pair spectra show a quasi-condensate at a nonzero momentum proportional to the polarization, as expected for this Fulde-Ferrel-Larkin-Ovchinnikov-like superfluid.

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Adrian E. Feiguin, David A. Huse. 2008-09-17. Spectral properties of a partially spin-polarized one-dimensional Hubbard/Luttinger superfluid. https://doi.org/10.1103/physrevb.79.100507

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