Orbital and valley state spectra of a few-electron silicon quantum dot

C. H. Yang, W. H. Lim, N. S. Lai, A. Rossi, A. Morello, A. S. Dzurak

Research output: Contribution to journalArticle

17 Citations (Scopus)

Abstract

Understanding interactions between orbital and valley quantum states in silicon nanodevices is crucial in assessing the prospects of spin-based qubits. We study the energy spectra of a few-electron silicon metal-oxide-semiconductor quantum dot using dynamic charge sensing and pulsed-voltage spectroscopy. The occupancy of the quantum dot is probed down to the single-electron level using a nearby single-electron transistor as a charge sensor. The energy of the first orbital excited state is found to decrease rapidly as the electron occupancy increases from N=1 to 4. By monitoring the sequential spin filling of the dot we extract a valley splitting of ∼230μeV, irrespective of electron number. This indicates that favorable conditions for qubit operation are in place in the few-electron regime. © 2012 American Physical Society.

Original languageEnglish
Article number115319
Number of pages5
JournalPhysical Review B - Condensed Matter and Materials Physics
Volume86
Issue number11
DOIs
Publication statusPublished - 12 Sep 2012

Fingerprint

Silicon
Semiconductor quantum dots
valleys
quantum dots
orbitals
Electrons
silicon
electrons
Single electron transistors
single electron transistors
silicon oxides
Excited states
metal oxide semiconductors
energy spectra
Metals
Spectroscopy
Monitoring
sensors
Sensors
Electric potential

Keywords

  • quantum dots
  • semiconductor quantum dots
  • spin blockade

Cite this

Yang, C. H. ; Lim, W. H. ; Lai, N. S. ; Rossi, A. ; Morello, A. ; Dzurak, A. S. / Orbital and valley state spectra of a few-electron silicon quantum dot. In: Physical Review B - Condensed Matter and Materials Physics. 2012 ; Vol. 86, No. 11.
@article{8ac3fe5bb97440219ffe3ace8d158bb4,
title = "Orbital and valley state spectra of a few-electron silicon quantum dot",
abstract = "Understanding interactions between orbital and valley quantum states in silicon nanodevices is crucial in assessing the prospects of spin-based qubits. We study the energy spectra of a few-electron silicon metal-oxide-semiconductor quantum dot using dynamic charge sensing and pulsed-voltage spectroscopy. The occupancy of the quantum dot is probed down to the single-electron level using a nearby single-electron transistor as a charge sensor. The energy of the first orbital excited state is found to decrease rapidly as the electron occupancy increases from N=1 to 4. By monitoring the sequential spin filling of the dot we extract a valley splitting of ∼230μeV, irrespective of electron number. This indicates that favorable conditions for qubit operation are in place in the few-electron regime. {\circledC} 2012 American Physical Society.",
keywords = "quantum dots, semiconductor quantum dots, spin blockade",
author = "Yang, {C. H.} and Lim, {W. H.} and Lai, {N. S.} and A. Rossi and A. Morello and Dzurak, {A. S.}",
year = "2012",
month = "9",
day = "12",
doi = "10.1103/PhysRevB.86.115319",
language = "English",
volume = "86",
journal = "Physical Review B: Condensed Matter and Materials Physics",
issn = "1098-0121",
number = "11",

}

Orbital and valley state spectra of a few-electron silicon quantum dot. / Yang, C. H.; Lim, W. H.; Lai, N. S.; Rossi, A.; Morello, A.; Dzurak, A. S.

In: Physical Review B - Condensed Matter and Materials Physics, Vol. 86, No. 11, 115319, 12.09.2012.

Research output: Contribution to journalArticle

TY - JOUR

T1 - Orbital and valley state spectra of a few-electron silicon quantum dot

AU - Yang, C. H.

AU - Lim, W. H.

AU - Lai, N. S.

AU - Rossi, A.

AU - Morello, A.

AU - Dzurak, A. S.

PY - 2012/9/12

Y1 - 2012/9/12

N2 - Understanding interactions between orbital and valley quantum states in silicon nanodevices is crucial in assessing the prospects of spin-based qubits. We study the energy spectra of a few-electron silicon metal-oxide-semiconductor quantum dot using dynamic charge sensing and pulsed-voltage spectroscopy. The occupancy of the quantum dot is probed down to the single-electron level using a nearby single-electron transistor as a charge sensor. The energy of the first orbital excited state is found to decrease rapidly as the electron occupancy increases from N=1 to 4. By monitoring the sequential spin filling of the dot we extract a valley splitting of ∼230μeV, irrespective of electron number. This indicates that favorable conditions for qubit operation are in place in the few-electron regime. © 2012 American Physical Society.

AB - Understanding interactions between orbital and valley quantum states in silicon nanodevices is crucial in assessing the prospects of spin-based qubits. We study the energy spectra of a few-electron silicon metal-oxide-semiconductor quantum dot using dynamic charge sensing and pulsed-voltage spectroscopy. The occupancy of the quantum dot is probed down to the single-electron level using a nearby single-electron transistor as a charge sensor. The energy of the first orbital excited state is found to decrease rapidly as the electron occupancy increases from N=1 to 4. By monitoring the sequential spin filling of the dot we extract a valley splitting of ∼230μeV, irrespective of electron number. This indicates that favorable conditions for qubit operation are in place in the few-electron regime. © 2012 American Physical Society.

KW - quantum dots

KW - semiconductor quantum dots

KW - spin blockade

UR - http://www.scopus.com/inward/record.url?scp=84866382903&partnerID=8YFLogxK

U2 - 10.1103/PhysRevB.86.115319

DO - 10.1103/PhysRevB.86.115319

M3 - Article

VL - 86

JO - Physical Review B: Condensed Matter and Materials Physics

JF - Physical Review B: Condensed Matter and Materials Physics

SN - 1098-0121

IS - 11

M1 - 115319

ER -