Dynamic Characterization and Impulse Response Modeling of Amplitude and Phase Response of Silicon Nanowires

Ciaran S. Cleary, Hua Ji, James M. Dailey, Roderick P. Webb, Robert J. Manning, Michael Galili, Palle Jeppesen, Minhao Pu, Kresten Yvind, Leif Katsuo Oxenløwe

Research output: Contribution to journalJournal articleResearchpeer-review


Amplitude and phase dynamics of silicon nanowires were measured using time-resolved spectroscopy. Time shifts of the maximum phase change and minimum amplitude as a function of pump power due to saturation of the free-carrier density were observed. A phenomenological impulse response model used to fit the experimental data indicated that the free-carrier lifetime was between $7.5 \leq \tau_{\rm fc} \leq 16.2\ \hbox{ns}$, and the two-photon absorption coefficient and the Kerr coefficient were $3 \times 10^{-12}\ \hbox{m.W}^{-1}$ and $4 \times 10^{-18}\ \hbox{m}^{2}.\hbox{W}^{-1}$, respectively, for silicon nanowires with lengths varying from 3.6 to 14.9 mm.
Original languageEnglish
JournalI E E E Photonics Journal
Issue number2
Pages (from-to)4500111
Number of pages11
Publication statusPublished - 2013


  • Silicon nanowire
  • Pump–probe spectroscopy
  • Two-photon absorption (TPA)
  • Free-carrier absorption (FCA)


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