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Quantum dot in the pseudogap Kondo state

J. Hopkinson·K. Le Hur·E. Dupont
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Abstract

We investigate the transport properties of a (small) quantum dot connected to Fermi liquid leads with a power-law density of states (DOS). Such a system, if experimentally realizable, will have interesting physical properties including: (i) non-saturating Coulomb blockade peak widths; (ii) a non-unitary Kondo peak symmetrically placed between the Coulomb blockade peaks; (iii) an absence of conductance away from particle-hole symmetry at sufficiently low temperatures; and (iv) evidence of a quantum critical point as a function of dot-lead hopping. These properties are compared and contrasted with one dimensional Luttinger systems exhibiting a power-law "tunneling-DOS".

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J. Hopkinson, K. Le Hur, E. Dupont. 2005-12-01. Quantum dot in the pseudogap Kondo state. https://doi.org/10.1140/epjb%2Fe2006-00013-5

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