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Competition of disorder and interchain hopping in a two-chain Hubbard model

E. Orignac·Y. Suzumura
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Abstract

We study the interplay of Anderson localization and interaction in a two chain Hubbard ladder allowing for arbitrary ratio of disorder strength to interchain coupling. We obtain three different types of spin gapped localized phases depending on the strength of disorder: a pinned $4k_F$ Charge Density Wave (CDW) for weak disorder, a pinned $2k_F$ CDW$^π$ for intermediate disorder and two independently pinned single chain $2k_F$ CDW for strong disorder. Confinement of electrons can be obtained as a result of strong disorder or strong attraction. We give the full phase diagram as a function of disorder, interaction strength and interchain hopping. We also study the influence of interchain hopping on localization length and show that localization is enhanced by a small interchain hopping but suppressed by a large interchain hopping.

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E. Orignac, Y. Suzumura. 2001-04-10. Competition of disorder and interchain hopping in a two-chain Hubbard model. https://doi.org/10.1007/s100510170082

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