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arXiv · 1411.5632

Negative differential conductivity in an interacting quantum gas

Ralf Labouvie·Bodhaditya Santra·Simon Heun·Sandro Wimberger·Herwig Ott
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Abstract

Negative differential conductivity (NDC) is a widely exploited effect in modern electronic components. Here, a proof-of-principle is given for the observation of NDC in a quantum transport device for neutral atoms employing a multi-mode tunneling junction. The transport of the many-body quantum system is governed by the interplay between the tunnel coupling, the interaction energy and the thermodynamics of intrinsic collisions, which turn the coherent coupling into a hopping process. The resulting current voltage characteristics exhibit NDC, for which we identify a new microscopic physical mechanism. Our study opens new ways for the future implementation and control of complex neutral atom quantum circuits.

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Ralf Labouvie, Bodhaditya Santra, Simon Heun, Sandro Wimberger, Herwig Ott. 2014-11-20. Negative differential conductivity in an interacting quantum gas. https://doi.org/10.1103/physrevlett.115.050601

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