Meny

Javascript verkar inte påslaget? - Vissa delar av Lunds universitets webbplats fungerar inte optimalt utan javascript, kontrollera din webbläsares inställningar.
Du är här

Structural and optical properties of high quality zinc-blende/wurtzite GaAs nanowire heterostructures

Författare:
Publiceringsår: 2009
Språk: Engelska
Sidor:
Publikation/Tidskrift/Serie: Physical Review B
Volym: 80
Nummer: 24
Dokumenttyp: Artikel
Förlag: American Physical Society

Sammanfattning

The structural and optical properties of three different kinds of GaAs nanowires with 100% zinc-blende structure and with an average of 30% and 70% wurtzite are presented. A variety of shorter and longer segments of zinc-blende or wurtzite crystal phases are observed by transmission electron microscopy in the nanowires. Sharp photoluminescence lines are observed with emission energies tuned from 1.515 eV down to 1.43 eV when the percentage of wurtzite is increased. The downward shift of the emission peaks can be understood by carrier confinement at the interfaces, in quantum wells and in random short period superlattices existent in these nanowires, assuming a staggered band offset between wurtzite and zinc-blende GaAs. The latter is confirmed also by time-resolved measurements. The extremely local nature of these optical transitions is evidenced also by cathodoluminescence measurements. Raman spectroscopy on single wires shows different strain conditions, depending on the wurtzite content which affects also the band alignments. Finally, the occurrence of the two crystallographic phases is discussed in thermodynamic terms.

Disputation

Nyckelord

  • Physics and Astronomy
  • semiconductor quantum wires
  • semiconductor quantum wells
  • semiconductor heterojunctions
  • Raman spectra
  • photoluminescence
  • nanowires
  • III-V semiconductors
  • cathodoluminescence
  • gallium arsenide
  • thermodynamics
  • time resolved spectra
  • transmission electron microscopy

Övriga

Published
Yes
  • ISSN: 1098-0121

Box 117, 221 00 LUND
Telefon 046-222 00 00 (växel)
Telefax 046-222 47 20
lu [at] lu [dot] se

Fakturaadress: Box 188, 221 00 LUND
Organisationsnummer: 202100-3211
Om webbplatsen