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arXiv · 0905.1281

Strongly Interacting Two-Dimensional Dirac Fermions

Lih-King Lim·Achilleas Lazarides·Andreas Hemmerich·C. Morais Smith
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Abstract

We show how strongly interacting two-dimensional Dirac fermions can be realized with ultracold atoms in a two-dimensional optical square lattice with an experimentally realistic, inherent gauge field, which breaks time-reversal and inversion symmetries. We find remarkable phenomena in a temperature range around a tenth of the Fermi-temperature, accessible with present experimental techniques: at zero chemical potential, besides a conventional s-wave superconducting phase, unconventional superconductivity with non-local bond pairing arises. In a temperature versus doping phase diagram, the unconventional superconducting phase exhibits a dome structure, reminiscent of the phase diagram for high-temperature superconductors and heavy fermions.

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Lih-King Lim, Achilleas Lazarides, Andreas Hemmerich, C. Morais Smith. 2009-05-08. Strongly Interacting Two-Dimensional Dirac Fermions. https://doi.org/10.1209/0295-5075/88/36001

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