Kondo Impurity in a Mesoscopic Ring

Charge Persistent Current

H. P. Eckle, H. Johannesson, Charles A Stafford

Research output: Contribution to journalArticle

11 Citations (Scopus)

Abstract

We study the influence of a magnetic impurity or ultrasmall quantum dot on the charge persistent current of a mesoscopic ring. The system consists of electrons in a one-dimensional ring threaded by spin-dependent Aharonov-Bohm/Casher fluxes, coupled via an antiferromagnetic exchange interaction to a localized electron. By passing to a basis of electron states with definite parities, the problem is mapped onto a Kondo model for the even-parity channel plus free electrons in the odd-parity channel. The twisted boundary conditions representing the fluxes couple states of opposite parity unless the twist angles satisfy φα = fαπ, where fα are integers, with spin index α = ↑, ↓. For these special values of φα, the model is solved exactly by a Bethe ansatz. Special cases are investigated in detail. In particular we show that the charge stiffness in the case φ = φ is insensitive to the presence of the magnetic impurity/quantum dot.

Original languageEnglish (US)
Pages (from-to)475-483
Number of pages9
JournalJournal of Low Temperature Physics
Volume118
Issue number5-6
StatePublished - 2000

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parity
Impurities
impurities
Semiconductor quantum dots
Electrons
rings
Fluxes
Exchange interactions
quantum dots
Electron energy levels
electron states
Stiffness
Boundary conditions
free electrons
integers
stiffness
electrons
boundary conditions
interactions

ASJC Scopus subject areas

  • Physics and Astronomy (miscellaneous)

Cite this

Kondo Impurity in a Mesoscopic Ring : Charge Persistent Current. / Eckle, H. P.; Johannesson, H.; Stafford, Charles A.

In: Journal of Low Temperature Physics, Vol. 118, No. 5-6, 2000, p. 475-483.

Research output: Contribution to journalArticle

Eckle, H. P. ; Johannesson, H. ; Stafford, Charles A. / Kondo Impurity in a Mesoscopic Ring : Charge Persistent Current. In: Journal of Low Temperature Physics. 2000 ; Vol. 118, No. 5-6. pp. 475-483.
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