Electronic states in silicon quantum dots

Multivalley artificial atoms

Yoko Hada, Mikio Eto

Research output: Contribution to journalArticle

46 Citations (Scopus)

Abstract

Electronic states in silicon quantum dots are examined theoretically, taking into account a multivalley structure of the conduction band. We find that (i) exchange interaction hardly works between electrons in different valleys. In consequence electrons occupy the lowest level in different valleys in the absence of Hund's coupling when the dot size is less than 10 nm. High-spin states are easily realized by applying a small magnetic field. (ii) When the dot size is much larger, the electron-electron interaction becomes relevant in determining the electronic states. Electrons are accommodated in a valley, making the highest spin, to gain the exchange energy. (iii) In the presence of intervalley scattering, degenerate levels in different valleys are split. This could result in low-spin states. These spin states in multivalley artificial atoms can be observed by looking at the magnetic-field dependence of peak positions in the Coulomb oscillation.

Original languageEnglish
Article number155322
Pages (from-to)1553221-1553227
Number of pages7
JournalPhysical Review B - Condensed Matter and Materials Physics
Volume68
Issue number15
Publication statusPublished - 2003 Oct

Fingerprint

Electronic states
Silicon
Semiconductor quantum dots
valleys
quantum dots
Atoms
Electrons
silicon
electronics
Magnetic fields
atoms
Electron-electron interactions
electrons
Exchange interactions
Conduction bands
magnetic fields
Scattering
conduction bands
electron scattering
energy transfer

ASJC Scopus subject areas

  • Condensed Matter Physics

Cite this

Electronic states in silicon quantum dots : Multivalley artificial atoms. / Hada, Yoko; Eto, Mikio.

In: Physical Review B - Condensed Matter and Materials Physics, Vol. 68, No. 15, 155322, 10.2003, p. 1553221-1553227.

Research output: Contribution to journalArticle

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