Entanglement of an impurity and conduction spins in the Kondo model

Sangchul Oh, Jaewan Kim

Research output: Contribution to journalArticle

15 Citations (Scopus)

Abstract

Based on Yosida's ground state of the single-impurity Kondo Hamiltonian, we study three kinds of entanglement between an impurity and conduction electron spins. First, it is shown that the impurity spin is maximally entangled with all the conduction electrons. Second, a two-spin density matrix of the impurity spin and one conduction electron spin is given by a Werner state. We find that the impurity spin is not entangled with one conduction electron spin even within the Kondo screening length ξK, although there is the spin-spin correlation between them. Third, we show the density matrix of two conduction electron spins is nearly the same as that of a free electron gas. The single impurity does not change the entanglement structure of the conduction electrons in contrast to the dramatic change in electrical resistance.

Original languageEnglish
Article number052407
JournalPhysical Review B - Condensed Matter and Materials Physics
Volume73
Issue number5
DOIs
Publication statusPublished - 2 Mar 2006
Externally publishedYes

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conduction electrons
Impurities
conduction
electron spin
impurities
Electrons
Hamiltonians
Electron gas
Acoustic impedance
electrical resistance
Ground state
free electrons
electron gas
Screening
screening
ground state
electrons

ASJC Scopus subject areas

  • Condensed Matter Physics

Cite this

Entanglement of an impurity and conduction spins in the Kondo model. / Oh, Sangchul; Kim, Jaewan.

In: Physical Review B - Condensed Matter and Materials Physics, Vol. 73, No. 5, 052407, 02.03.2006.

Research output: Contribution to journalArticle

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