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arXiv · 0708.1304

Interaction-Induced Strong Localization in Quantum Dots

A. D. Guclu·A. Ghosal·C. J. Umrigar·H. U. Baranger
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Abstract

We argue that Coulomb blockade phenomena are a useful probe of the cross-over to strong correlation in quantum dots. Through calculations at low density using variational and diffusion quantum Monte Carlo (up to r_s ~ 55), we find that the addition energy shows a clear progression from features associated with shell structure to those caused by commensurability of a Wigner crystal. This cross-over (which occurs near r_s ~ 20 for spin-polarized electrons) is, then, a signature of interaction-driven localization. As the addition energy is directly measurable in Coulomb blockade conductance experiments, this provides a direct probe of localization in the low density electron gas.

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A. D. Guclu, A. Ghosal, C. J. Umrigar, H. U. Baranger. 2009-08-10. Interaction-Induced Strong Localization in Quantum Dots. https://doi.org/10.1103/physrevb.77.041301

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