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arXiv · 1109.5731

The Fermi liquid nature of the ground state of double quantum dots in parallel from a 1/N expansion

Manas Kulkarni·Robert Konik
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Abstract

A large-N diagrammatic approach is used to study coupled quantum dots in a parallel geometry. We show that the Friedel sum rule (FSR) holds at lowest order in a 1/N expansion for this system, thereby suggesting that the ground state is a Fermi liquid. Using the FSR together with the dot occupancy, we compute the dot system's conductance. Our finding that the 1/N expansion indicates the system is a Fermi liquid is in agreement with both prior results based on the Bethe ansatz and slave boson mean field theory.

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Manas Kulkarni, Robert Konik. 2011-09-26. The Fermi liquid nature of the ground state of double quantum dots in parallel from a 1/N expansion. https://arxiv.org/abs/1109.5731

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