Kondo effect in coupled quantum dots under magnetic fields

T. Aono, Mikio Eto

Research output: Contribution to journalArticle

18 Citations (Scopus)

Abstract

The Kondo effect in coupled quantum dots is investigated theoretically under magnetic fields. We show that the magnetoconductance (MC) illustrates the peak structures of Kondo resonant spectra. When the dot-dot tunneling coupling Vc is smaller than the dot-lead coupling Δ (level broadening), Kondo resonant levels appear at the Fermi level (EF). The Zeeman splitting of the levels weakens the Kondo effect, which results in a negative MC. When Vc is larger thanΔ, the Kondo resonances form bonding and antibonding levels, located below and above EF, respectively. We observe a positive MC since the Zeeman splitting increases the overlap between the levels at EF. In the presence of antiferromagnetic spin coupling between the dots, the sign of the MC can change as a function of the gate voltage.

Original languageEnglish
Article number073307
Pages (from-to)733071-733074
Number of pages4
JournalPhysical Review B - Condensed Matter and Materials Physics
Volume64
Issue number7
Publication statusPublished - 2001 Aug 15

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Kondo effect
Semiconductor quantum dots
quantum dots
Magnetic fields
Fermi level
magnetic fields
Lead
Electric potential
electric potential

ASJC Scopus subject areas

  • Condensed Matter Physics

Cite this

Kondo effect in coupled quantum dots under magnetic fields. / Aono, T.; Eto, Mikio.

In: Physical Review B - Condensed Matter and Materials Physics, Vol. 64, No. 7, 073307, 15.08.2001, p. 733071-733074.

Research output: Contribution to journalArticle

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