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arXiv · 1706.02679

Tuning the Drude weight of Dirac-Weyl fermions in one-dimensional ring traps

Manon Bischoff·Johannes Jünemann·Marco Polini·Matteo Rizzi
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Abstract

We study the response to an applied flux of an interacting system of Dirac-Weyl fermions confined in a one-dimensional (1D) ring. Combining analytical calculations with density-matrix renormalization group results, we show that tuning of interactions leads to a unique many-body system that displays either a suppression or an enhancement of the Drude weight - the zero-frequency peak in the ac conductivity - with respect to the non-interacting value. An asymmetry in the interaction strength between same- and different-pseudospin Dirac-Weyl fermions leads to Drude weight enhancement. Viceversa, symmetric interactions lead to Drude weight suppression. Our predictions can be tested in mixtures of ultracold fermions in 1D ring traps.

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Manon Bischoff, Johannes Jünemann, Marco Polini, Matteo Rizzi. 2018-01-06. Tuning the Drude weight of Dirac-Weyl fermions in one-dimensional ring traps. https://doi.org/10.1103/physrevb.96.241112

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