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arXiv · 0708.0894

Density-Matrix Renormalization Group Study of Trapped Imbalanced Fermi Condensates

Masaki Tezuka·Masahito Ueda
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Abstract

The density-matrix renormalization group is employed to investigate a harmonically-trapped imbalanced Fermi condensate based on a one-dimensional attractive Hubbard model. The obtained density profile shows a flattened population difference of spin-up and spin-down components at the center of the trap, and exhibits phase separation between the condensate and unpaired majority atoms for a certain range of the interaction and population imabalance $P$. The two-particle density matrix reveals that the sign of the order parameter changes periodically, demonstrating the realization of the Fulde-Ferrell-Larkin-Ovchinnikov phase. The minority spin atoms contribute to the quasi-condensate up to at least $P \simeq 0.8$. Possible experimental situations to test our predictions are discussed.

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Masaki Tezuka, Masahito Ueda. 2008-02-07. Density-Matrix Renormalization Group Study of Trapped Imbalanced Fermi Condensates. https://doi.org/10.1103/physrevlett.100.110403

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