Kondo effect in silicon quantum dots with valley degeneracy

Mikio Eto, Y. Hada

Research output: Chapter in Book/Report/Conference proceedingConference contribution

4 Citations (Scopus)

Abstract

We theoretically examine electronic states and Kondo effect in silicon quantum dots, taking into account a multivalley structure of conduction band. In the quantum dots, discrete energy levels are almost degenerate owing to two equivalent valleys. When an electron occupies the levels, an enhanced Kondo effect of SU(4) symmetry is expected. When two electrons are accommodated in a quantum dot, three spin-singlet and one spin-triplet states can be six-fold degenerate since the exchange integral is negligible when the dot size is much larger than the lattice constant of silicon. An underscreening Kondo effect involving these states is realized if tunnel couplings are equivalent for the levels. Otherwise, a "two-stage Kondo effect" is observed as a function of temperature, reflecting two independent SU(2) Kondo effects.

Original languageEnglish
Title of host publicationAIP Conference Proceedings
Pages1382-1383
Number of pages2
Volume850
DOIs
Publication statusPublished - 2006
EventLOW TEMPERATURE PHYSICS: 24th International Conference on Low Temperature Physics - LT24 - Orlando, FL, United States
Duration: 2006 Aug 102006 Oct 17

Other

OtherLOW TEMPERATURE PHYSICS: 24th International Conference on Low Temperature Physics - LT24
CountryUnited States
CityOrlando, FL
Period06/8/1006/10/17

Fingerprint

Kondo effect
valleys
quantum dots
silicon
atomic energy levels
tunnels
conduction bands
electrons
energy levels
symmetry
electronics
temperature

Keywords

  • Kondoeffect
  • Multivalley
  • Quantumdot
  • Silicon

ASJC Scopus subject areas

  • Physics and Astronomy(all)

Cite this

Eto, M., & Hada, Y. (2006). Kondo effect in silicon quantum dots with valley degeneracy. In AIP Conference Proceedings (Vol. 850, pp. 1382-1383) https://doi.org/10.1063/1.2355221

Kondo effect in silicon quantum dots with valley degeneracy. / Eto, Mikio; Hada, Y.

AIP Conference Proceedings. Vol. 850 2006. p. 1382-1383.

Research output: Chapter in Book/Report/Conference proceedingConference contribution

Eto, M & Hada, Y 2006, Kondo effect in silicon quantum dots with valley degeneracy. in AIP Conference Proceedings. vol. 850, pp. 1382-1383, LOW TEMPERATURE PHYSICS: 24th International Conference on Low Temperature Physics - LT24, Orlando, FL, United States, 06/8/10. https://doi.org/10.1063/1.2355221
Eto M, Hada Y. Kondo effect in silicon quantum dots with valley degeneracy. In AIP Conference Proceedings. Vol. 850. 2006. p. 1382-1383 https://doi.org/10.1063/1.2355221
Eto, Mikio ; Hada, Y. / Kondo effect in silicon quantum dots with valley degeneracy. AIP Conference Proceedings. Vol. 850 2006. pp. 1382-1383
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