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arXiv · 1207.3426

Non-local order parameters for the 1D Hubbard model

Arianna Montorsi·Marco Roncaglia
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Abstract

We characterize the Mott insulator and Luther-Emery phases of the 1D Hubbard model through correlators that measure the parity of spin and charge strings along the chain. These non-local quantities order in the corresponding gapped phases and vanish at the critical point $U_c=0$. The Mott insulator consists of bound doublon-holon pairs, which in the Luther-Emery phase turn into electron pairs with opposite spins, both unbinding at $U_c$. The behavior of the parity correlators can be captured by an effective free spinless fermion model.

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Arianna Montorsi, Marco Roncaglia. 2012-07-24. Non-local order parameters for the 1D Hubbard model. https://doi.org/10.1103/physrevlett.109.236404

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