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arXiv · 1503.06296

Interaction-induced Drude weight enhancement in frustrated systems

Vipin Kerala Varma·Ramsés Sánchez
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Abstract

We investigate the effect of next nearest-neighbour hopping on the zero temperature Drude weight or superfluidity in mesoscopic one-dimensional systems of (a) single particle with quasidisorder (Aubry-André model) and (b) hardcore bosons with nearest-neighbour interaction. We show that there is an interaction-induced enhancement of the Drude weight when the next nearest-neighbour hopping is frustrated for the many-body system. The observed non-monotonic behaviour of the Drude weight occurs because the repulsive interactions first suppress the frustration in the system, leading to a rise in the Drude weight, whereas at much larger interaction strengths the charge density wave fluctuations set in the insulator and the Drude weight drops. The present work reveals a novel scenario in which a persistent flow enhancement is plausible in the presence of kinetic frustration and repulsive interactions.

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Vipin Kerala Varma, Ramsés Sánchez. 2015-07-13. Interaction-induced Drude weight enhancement in frustrated systems. https://doi.org/10.1103/physreva.92.013618

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