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arXiv · 2205.12233

Site-resolved observables in the doped spin-imbalanced triangular Hubbard model

Abstract

The suppression of antiferromagnetic ordering in geometrically frustrated Hubbard models leads to a variety of exotic quantum phases including quantum spin liquids and chiral states. Here, we focus on the Hubbard model on one of the simplest frustrated lattice geometries, a triangular lattice. Motivated by the recent realization of ultracold fermionic atoms in triangular optical lattices, we study the properties of the triangular-lattice Hubbard model through a Numerical Linked-Cluster Expansion algorithm. We investigate the Mott insulator transition finding a critical interaction $U_c/t = 7.0(2)$ and use spatial two- and three-point correlation functions to explore doped and imbalanced systems. Our results demonstrate that many interesting features occur at temperatures previously obtained for ultracold fermions in optical lattices and are accessible by upcoming experiments. Our calculations will be helpful for thermometry in ultracold atom quantum simulators and can guide experimental searches for exotic quantum phases in atomic triangular Hubbard quantum simulators.

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Davis Garwood, Jirayu Mongkolkiattichai, Liyu Liu, Jin Yang, Peter Schauss. 2022-05-24. Site-resolved observables in the doped spin-imbalanced triangular Hubbard model. https://doi.org/10.1103/physreva.106.013310

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