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arXiv:0902.2463

Emergence of Topological Fermi Liquid from a Strongly Correlated Bosonic System in Optical Superlattices

Bo-Lun Chen, Su-Peng Kou

Published Feb 14, 2009• 0 citations
arXivHTMLPDF

Abstract

Recent experiments on quantum degenerate gases give an opportunity for simulating strongly-correlated electronic systems in optical lattices. It may shed light on some long-standing puzzles in condensed-matter physics, like the nature of high-temperature superconductivity in cuprates that had baffled people over two decades. It is believed that the two-dimensional fermionic Hubbard model, or t-J model, contains the key to this problem; but the difficulty of unveiling the mystery of a strongly-interacting fermionic system is also generally acknowledged. Here, as a substitute, we systematically analyze the property of bosonic t-J model simulated in optical superlattices near unit-filling. In particular, we show the emergence of a strange topological Fermi liquid with Fermi surfaces from a purely bosonic system. We also discuss the possibility of observing these phenomena in ultracold atom experiments. The result may provide some crucial insights into the origin of high-T_{c} superconductivity.

DOI
10.48550/arxiv.0902.2463

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Recent experiments on quantum degenerate gases give an opportunity for simulating strongly-correlated electronic systems in optical lattices. It may shed light on some long-standing puzzles in condensed-matter physics, like the nature of high-temperature superconductivity in cuprates that had baffled people over two decades. It is believed that the two-dimensional fermionic Hubbard model, or t-J model, contains the key to this problem; but the difficulty of unveiling the mystery of a strongly-interacting fermionic system is also generally acknowledged. Here, as a substitute, we systematically analyze the property of bosonic t-J model simulated in optical superlattices near unit-filling. In particular, we show the emergence of a strange topological Fermi liquid with Fermi surfaces from a purely bosonic system. We also discuss the possibility of observing these phenomena in ultracold atom experiments. The result may provide some crucial insights into the origin of high-T_{c} superconductivity.
Ultracold atomic gases provide a fantastic platform to implement quantum simulators and investigate a variety of models initially introduced in condensed matter physics or other areas. One of the most promising applications of quantum simulation is the study of strongly correlated Fermi gases, for which exact theoretical results are not always possible with state-of-the-art approaches. Here, we review recent progress of the quantum simulation of the emblematic Fermi–Hubbard model with ultracold atoms. After introducing the Fermi–Hubbard model in the context of condensed matter, its implementation in ultracold atom systems, and its phase diagram, we review landmark experimental achievements, from the early observation of the onset of quantum degeneracy and superfluidity to the demonstration of the Mott insulator regime and the emergence of long-range anti-ferromagnetic order. We conclude by discussing future challenges, including the possible observation of high- T c superconductivity, transport properties, and the interplay of strong correlations and disorder or topology.
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