Ändra sökning
RefereraExporteraLänk till posten
Permanent länk

Direktlänk
Referera
Referensformat
  • apa
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Annat format
Fler format
Språk
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Annat språk
Fler språk
Utmatningsformat
  • html
  • text
  • asciidoc
  • rtf
Aluminum-Induced Photoluminescence Red Shifts in Core-Shell GaAs/AlxGa1-xAs Nanowires
Aalto University.
Aalto University.
Aalto University.
Aalto University.
Visa övriga samt affilieringar
2013 (Engelska)Ingår i: Nano letters (Print), ISSN 1530-6984, E-ISSN 1530-6992, Vol. 13, nr 8, s. 3581-3588Artikel i tidskrift (Refereegranskat) Published
Abstract [en]

We report a new phenomenon related to Al-induced carrier confinement at the interface in core-shell GaAs/AlxGa1-xAs nanowires grown using metal-organic vapor phase epitaxy with Au as catalyst. All AlxGa1-xAs shells strongly passivated the GaAs nanowires, but surprisingly the peak photoluminescence (PL) position and the intensity from the core were found to be a strong function of Al composition in the shell at low temperatures. Large and systematic red shifts of up to similar to 66 nm and broadening in the PL emission from the GaAs core were observed when the Al composition in the shell exceeded 3%. On the contrary, the phenomenon was observed to be considerably weaker at the room temperature. Cross-sectional transmission electron microscopy reveals Al segregation in the shell along six Al-rich radial bands displaying a 3-fold symmetry. Time-resolved PL measurements suggest the presence of indirect electron-hole transitions at the interface at higher Al composition. We discuss all possibilities including a simple shell-core-shell model using simulations where the density of interface traps increases with the Al content, thus creating a strong local electron confinement. The carrier confinement at the interface is most likely related to Al inhomogeneity and/or Al-induced traps. Our results suggest that a low Al composition in the shell is desirable in order to achieve ideal passivation in GaAs nanowires.

Ort, förlag, år, upplaga, sidor
2013. Vol. 13, nr 8, s. 3581-3588
Nyckelord [en]
GaAs/AlGaAs, core-shell nanowires, MOVPE, MOCVD, Al segregation, TRPL
Nationell ämneskategori
Atom- och molekylfysik och optik Nanoteknik
Identifikatorer
URN: urn:nbn:se:kth:diva-127413DOI: 10.1021/nl4012613ISI: 000323241000021Scopus ID: 2-s2.0-84881584613OAI: oai:DiVA.org:kth-127413DiVA, id: diva2:644084
Forskningsfinansiär
VetenskapsrådetEU, FP7, Sjunde ramprogrammet
Anmärkning

QC 20130913

Tillgänglig från: 2013-08-29 Skapad: 2013-08-29 Senast uppdaterad: 2017-12-06Bibliografiskt granskad

Open Access i DiVA

Fulltext saknas i DiVA

Övriga länkar

Förlagets fulltextScopus

Personposter BETA

Sanatinia, Reza

Sök vidare i DiVA

Av författaren/redaktören
Sanatinia, RezaAnand, Srinivasan
Av organisationen
Halvledarmaterial, HMAHalvledarmaterial, HMA (Stängd 20120101)
I samma tidskrift
Nano letters (Print)
Atom- och molekylfysik och optikNanoteknik

Sök vidare utanför DiVA

GoogleGoogle Scholar

doi
urn-nbn

Altmetricpoäng

doi
urn-nbn
Totalt: 391 träffar
RefereraExporteraLänk till posten
Permanent länk

Direktlänk
Referera
Referensformat
  • apa
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Annat format
Fler format
Språk
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Annat språk
Fler språk
Utmatningsformat
  • html
  • text
  • asciidoc
  • rtf