Laser-induced fano resonance scattering in silicon nanowires

R. Gupta, Q. Xiong, Kofi W. Adu, U. J. Kim, P. C. Eklund

Research output: Contribution to journalArticle

143 Citations (Scopus)

Abstract

We have studied the impact of excitation laser power density on the Raman spectrum of small-diameter (5-15 nm) silicon nanowires. At low power densities, a Lorentzian line is observed at 520 cm-1, the same value as that of the zone center LO (TO) phonon in bulk silicon. With increasing laser illumination, the Raman band downshifts and asymmetrically broadens on the low-frequency side. Our results contradict the traditionally accepted notion that a downshifted and asymmetrically broadened line in Si nanowires is due to quantum confinement effects. Rather, we suggest that the downshifting can be due to a laser heating effect of the nanowire and that the asymmetric line shape is due to a Fano interference between scattering from the k = 0 optic phonon and electronic continuum scattering from laser-induced electrons in the conduction band.

Original languageEnglish (US)
Pages (from-to)627-631
Number of pages5
JournalNano letters
Volume3
Issue number5
DOIs
StatePublished - May 1 2003

Fingerprint

resonance scattering
Silicon
Nanowires
nanowires
Scattering
Lasers
radiant flux density
silicon
lasers
Laser heating
Laser excitation
Quantum confinement
laser heating
Conduction bands
scattering
line shape
Raman scattering
Optics
conduction bands
Lighting

All Science Journal Classification (ASJC) codes

  • Bioengineering
  • Chemistry(all)
  • Materials Science(all)
  • Condensed Matter Physics
  • Mechanical Engineering

Cite this

Gupta, R. ; Xiong, Q. ; Adu, Kofi W. ; Kim, U. J. ; Eklund, P. C. / Laser-induced fano resonance scattering in silicon nanowires. In: Nano letters. 2003 ; Vol. 3, No. 5. pp. 627-631.
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Gupta, R, Xiong, Q, Adu, KW, Kim, UJ & Eklund, PC 2003, 'Laser-induced fano resonance scattering in silicon nanowires', Nano letters, vol. 3, no. 5, pp. 627-631. https://doi.org/10.1021/nl0341133

Laser-induced fano resonance scattering in silicon nanowires. / Gupta, R.; Xiong, Q.; Adu, Kofi W.; Kim, U. J.; Eklund, P. C.

In: Nano letters, Vol. 3, No. 5, 01.05.2003, p. 627-631.

Research output: Contribution to journalArticle

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T1 - Laser-induced fano resonance scattering in silicon nanowires

AU - Gupta, R.

AU - Xiong, Q.

AU - Adu, Kofi W.

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AU - Eklund, P. C.

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