Tunneling of a heavy particle with spin in a metal

Research output: Contribution to journalArticle

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Abstract

The low-temperature behavior of a two-level system (TLS) with spin is investigated, where the atom tunneling between two positions possesses a spin and interacts with the conduction electrons by an exchange interaction. To describe the physical properties of this TLS a generalized model is developed, where in addition to the usual screening and electron assisted tunneling processes exchange interaction and exchange assisted interactions with the conduction electrons are introduced. These exchange interaction terms break the SU(2) symmetry of the original TLS model corresponding to the conduction-electron spin. Summing up the leading logarithmic vertex corrections we show that if the Kondo temperature associated with the orbital degrees of freedom, TKorb, is smaller than that associated with the exchange interaction, TKmagn, then the orbital degrees of freedom of the TLS are frozen out when the magnetic Kondo effect takes place and only a magnetic Kondo effect occurs. In this case the ground state of the system seems to be a Fermi-liquid state. In the opposite case, TKorbTKmagn, two orbital electron channels become dominant below TKorb and a new fixed point appears. The possibility of experimental realizations is also shortly discussed.

Original languageEnglish
Pages (from-to)13459-13470
Number of pages12
JournalPhysical Review B
Volume52
Issue number18
DOIs
Publication statusPublished - 1995

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Exchange interactions
Metals
Electrons
conduction electrons
Kondo effect
metals
interactions
degrees of freedom
Fermi liquids
orbitals
electron orbitals
Degrees of freedom (mechanics)
electron spin
Ground state
Screening
apexes
screening
Physical properties
physical properties
Atoms

ASJC Scopus subject areas

  • Condensed Matter Physics

Cite this

Tunneling of a heavy particle with spin in a metal. / Zaránd, G.

In: Physical Review B, Vol. 52, No. 18, 1995, p. 13459-13470.

Research output: Contribution to journalArticle

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