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Optics Express

Optics Express

  • Editor: C. Martijn de Sterke
  • Vol. 17, Iss. 20 — Sep. 28, 2009
  • pp: 17450–17456

Probing the momentum relaxation time of charge carriers in ultrathin layers with terahertz radiation

Stefan Funk, Guillermo Acuna, Matthias Handloser, and Roland Kersting  »View Author Affiliations

Optics Express, Vol. 17, Issue 20, pp. 17450-17456 (2009)

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We report on the development of a terahertz time-domain technique for measuring the momentum relaxation time of charge carriers in ultrathin semiconductor layers. Making use of the Drude model, our phase sensitive modulation technique directly provides the relaxation time. Time-resolved THz experiments were performed on n-doped GaAs and show precise agreement with data obtained by electrical characterization. The technique is well suited for studying novel materials where parameters such as the charge carriers’ effective mass or the carrier density are not known a priori.

© 2009 OSA

OCIS Codes
(160.6000) Materials : Semiconductor materials
(300.6495) Spectroscopy : Spectroscopy, teraherz

ToC Category:

Original Manuscript: August 12, 2009
Revised Manuscript: September 14, 2009
Manuscript Accepted: September 14, 2009
Published: September 15, 2009

Stefan Funk, Guillermo Acuna, Matthias Handloser, and Roland Kersting, "Probing the momentum relaxation time of charge carriers in ultrathin layers with terahertz radiation," Opt. Express 17, 17450-17456 (2009)

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