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Giant Enhancement of the Thermo-Particle Transport Figure of Merit and Breakdown of the Wiedemann-Franz Law in Unitary Fermi Gases

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 نشر من قبل Xinloong Han
 تاريخ النشر 2018
  مجال البحث فيزياء
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We theoretically investigate the thermo-particle transport properties of an unitary Fermi gas be- tween two reservoirs connected by a quantum point contact. We find several distinguished properties that are qualitatively different from those of weak or non-interacting gas systems. The particle trans- port figure of merit is drastically enhanced in the unitary regime and it increases as the transmission coefficient increases, exactly opposite to the behavior in the weak or non-interacting gas systems. The Lorentz number violates the Wiedemann-Franz law, demonstrating the breakdown of Fermi liquid. These transport properties are the hallmarks of the unitary Fermi gas and are attributed to the existence of preformed Cooper pairs.



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