Numerical renormalization group studies of SU(4) Kondo effect in quantum dots

Tomoya Sato, Mikio Eto

Research output: Contribution to journalArticle

7 Citations (Scopus)

Abstract

We theoretically study an enhancement of the Kondo effect in quantum dots with two orbitals and spin 12. The Kondo temperature and conductance are evaluated as functions of energy difference Δ between the orbitals, using the numerical renormalization group method. The Kondo temperature is maximal around the degeneracy point (Δ=0) and decreases with increasing |Δ| following a power law, TK(Δ)=TK(0)(TK(0)/|Δ|)γ, which is consistent with the scaling analysis. The conductance at T=0 is almost constant 2e2/h. Both the orbitals contribute to the conductance around Δ=0, whereas the current through the upper orbital is negligibly small when |Δ|≳TK(0). These are characteristics of SU(4) Kondo effect.

Original languageEnglish
Pages (from-to)652-655
Number of pages4
JournalPhysica E: Low-Dimensional Systems and Nanostructures
Volume29
Issue number3-4
DOIs
Publication statusPublished - 2005 Nov

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Kondo effect
Semiconductor quantum dots
quantum dots
orbitals
Temperature
renormalization group methods
scaling
temperature
augmentation
energy

Keywords

  • Kondo effect
  • Numerical renormalization group
  • Quantum dot

ASJC Scopus subject areas

  • Electronic, Optical and Magnetic Materials
  • Condensed Matter Physics

Cite this

Numerical renormalization group studies of SU(4) Kondo effect in quantum dots. / Sato, Tomoya; Eto, Mikio.

In: Physica E: Low-Dimensional Systems and Nanostructures, Vol. 29, No. 3-4, 11.2005, p. 652-655.

Research output: Contribution to journalArticle

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