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arXiv · 1205.0404

Dimensional-crossover-driven Mott transition in the frustrated Hubbard model

Marcin Raczkowski·Fakher F. Assaad
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Abstract

We study the Mott transition in a frustrated Hubbard model with next-nearest neighbor hopping at half-filling. The interplay between interaction, dimensionality and geometric frustration closes the one-dimensional Mott gap and gives rise to a metallic phase with Fermi surface pockets. We argue that they emerge as a consequence of remnant one-dimensional Umklapp scattering at the momenta with vanishing interchain hopping matrix elements. In this pseudogap phase, enhanced d-wave pairing correlations are driven by antiferromagnetic fluctuations. Within the adopted cluster dynamical mean-field theory on the $8\times 2$ cluster and down to our lowest temperatures the transition from one to two dimensions is continuous.

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Marcin Raczkowski, Fakher F. Assaad. 2012-07-23. Dimensional-crossover-driven Mott transition in the frustrated Hubbard model. https://doi.org/10.1103/physrevlett.109.126404

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