OSA's Digital Library

Optics Express

Optics Express

  • Editor: C. Martijn de Sterke
  • Vol. 20, Iss. 16 — Jul. 30, 2012
  • pp: 18016–18024

Carrier density dependence of the nonlinear absorption of intense THz radiation in GaAs

G. Sharma, I. Al-Naib, H. Hafez, R. Morandotti, D. G. Cooke, and T. Ozaki  »View Author Affiliations

Optics Express, Vol. 20, Issue 16, pp. 18016-18024 (2012)

View Full Text Article

Enhanced HTML    Acrobat PDF (907 KB)

Browse Journals / Lookup Meetings

Browse by Journal and Year


Lookup Conference Papers

Close Browse Journals / Lookup Meetings

Article Tools



We study the carrier density dependence of nonlinear terahertz (THz) absorption due to field-induced intervalley scattering in photoexcited GaAs using the optical-pump/THz-probe technique. The intervalley scattering in GaAs is strongly dependent on the photo-carrier density. As the carrier density is increased from 1 × 1017 to 4.7 × 1017 cm−3, the nonlinear absorption bleaching increases. However, if the carrier density is increased further above 4.7 × 1017 cm−3, the trend reverses and the bleaching is reduced. The initial increase in absorption bleaching is because, unlike low THz field, high THz field experiences intervalley scattering and nonparabolicity of the conduction band. On the other hand, a simple electron transport model shows that the reduction in intervalley scattering is mainly due to the increase in the electron-hole scattering rate with the increase in the carrier density. This increase in the electron-hole scattering rate limits the maximum kinetic energy attainable by the electrons and thus reduces the observed nonlinear absorption.

© 2012 OSA

OCIS Codes
(300.6500) Spectroscopy : Spectroscopy, time-resolved
(320.7110) Ultrafast optics : Ultrafast nonlinear optics
(320.7130) Ultrafast optics : Ultrafast processes in condensed matter, including semiconductors
(300.6495) Spectroscopy : Spectroscopy, teraherz

ToC Category:
Ultrafast Optics

Original Manuscript: April 27, 2012
Revised Manuscript: July 5, 2012
Manuscript Accepted: July 6, 2012
Published: July 23, 2012

G. Sharma, I. Al-Naib, H. Hafez, R. Morandotti, D. G. Cooke, and T. Ozaki, "Carrier density dependence of the nonlinear absorption of intense THz radiation in GaAs," Opt. Express 20, 18016-18024 (2012)

Sort:  Author  |  Year  |  Journal  |  Reset  


  1. A. G. Markelz, N. G. Asmar, B. Brar, and E. G. Gwinn, “Interband impact ionization by terahertz illumination of InAs heterostructures,” Appl. Phys. Lett.69(26), 3975–3977 (1996). [CrossRef]
  2. S. D. Ganichev and W. Prettl, Intense Terahertz Excitation of Semiconductors (Oxford University Press, 2006).
  3. A. Mayer and F. Keilmann, “Far-infrared nonlinear optics. II. χ (3) contributions from the dynamics of free carriers in semiconductors,” Phys. Rev. B Condens. Matter33(10), 6962–6968 (1986). [CrossRef] [PubMed]
  4. A. G. Markelz and E. G. Gwinn, “Nonlinear response of quantum-confined electrons in nonparabolic subbands,” J. Appl. Phys.80(4), 2533–2535 (1996). [CrossRef]
  5. K. B. Nordstrom, K. Johnsen, S. J. Allen, A. P. Jauho, B. Birnir, J. Kono, T. Noda, H. Akiyama, and H. Sakaki, “Excitonic dynamical Franz-Keldysh effect,” Phys. Rev. Lett.81(2), 457–460 (1998). [CrossRef]
  6. B. E. Cole, J. B. Williams, B. T. King, M. S. Sherwin, and C. R. Stanley, “Coherent manipulation of semiconductor quantum bits with terahertz radiation,” Nature410(6824), 60–63 (2001). [CrossRef] [PubMed]
  7. P. Gaal, K. Reimann, M. Woerner, T. Elsaesser, R. Hey, and K. H. Ploog, “Nonlinear terahertz response of n-type GaAs,” Phys. Rev. Lett.96(18), 187402 (2006). [CrossRef] [PubMed]
  8. Y. Shen, T. Watanabe, D. A. Arena, C. C. Kao, J. B. Murphy, T. Y. Tsang, X. J. Wang, and G. L. Carr, “Nonlinear cross-phase modulation with intense single-cycle terahertz pulses,” Phys. Rev. Lett.99(4), 043901 (2007). [CrossRef] [PubMed]
  9. K. L. Yeh, M. C. Hoffmann, J. Hebling, and K. A. Nelson, “Generation of 10 μJ ultrashort terahertz pulses by optical rectification,” Appl. Phys. Lett.90(17), 171121 (2007). [CrossRef]
  10. F. Blanchard, L. Razzari, H. C. Bandulet, G. Sharma, R. Morandotti, J. C. Kieffer, T. Ozaki, M. Reid, H. F. Tiedje, H. K. Haugen, and F. A. Hegmann, “Generation of 1.5 µJ single-cycle terahertz pulses by optical rectification from a large aperture ZnTe crystal,” Opt. Express15(20), 13212–13220 (2007). [CrossRef] [PubMed]
  11. K.-Y. Kim, J. H. Glownia, A. J. Taylor, and G. Rodriguez, “Terahertz emission from ultrafast ionizing air in symmetry-broken laser fields,” Opt. Express15(8), 4577–4584 (2007). [CrossRef] [PubMed]
  12. J. Á. Hebling, K.-L. Yeh, M. C. Hoffmann, and K. A. Nelson, “High-power THz generation, THz nonlinear optics and THz nonlinear spectroscopy,” IEEE J. Sel. Top. Quantum Electron.14(2), 345–353 (2008). [CrossRef]
  13. A. G. Stepanov, L. Bonacina, S. V. Chekalin, and J.-P. Wolf, “Generation of 30 μJ single-cycle terahertz pulses at 100 Hz repetition rate by optical rectification,” Opt. Lett.33(21), 2497–2499 (2008). [CrossRef] [PubMed]
  14. P. Gaal, W. Kuehn, K. Reimann, M. Woerner, T. Elsaesser, R. Hey, J. S. Lee, and U. Schade, “Carrier-wave Rabi flopping on radiatively coupled shallow donor transitions in n - type GaAs,” Phys. Rev. B77(23), 235204 (2008). [CrossRef]
  15. H. Wen, M. Wiczer, and A. M. Lindenberg, “Ultrafast electron cascades in semiconductors driven by intense femtosecond terahertz pulses,” Phys. Rev. B78(12), 125203 (2008). [CrossRef]
  16. M. C. Hoffmann, J. Hebling, H. Y. Hwang, K.-L. Yeh, and K. A. Nelson, “Impact ionization in InSb probed by terahertz pump-terahertz probe spectroscopy,” Phys. Rev. B79(16), 161201 (2009). [CrossRef]
  17. F. Blanchard, D. Golde, F. H. Su, L. Razzari, G. Sharma, R. Morandotti, T. Ozaki, M. Reid, M. Kira, S. W. Koch, and F. A. Hegmann, “Effective mass anisotropy of hot electrons in nonparabolic conduction bands of n-doped InGaAs films using ultrafast terahertz pump-probe techniques,” Phys. Rev. Lett.107(10), 107401 (2011). [CrossRef] [PubMed]
  18. L. Razzari, F. H. Su, G. Sharma, F. Blanchard, A. Ayesheshim, H. C. Bandulet, R. Morandotti, J. C. Kieffer, T. Ozaki, M. Reid, and F. A. Hegmann, “Nonlinear ultrafast modulation of the optical absorption of intense few-cycle terahertz pulses in n - doped semiconductors,” Phys. Rev. B79(19), 193204 (2009). [CrossRef]
  19. F. H. Su, F. Blanchard, G. Sharma, L. Razzari, A. Ayesheshim, T. L. Cocker, L. V. Titova, T. Ozaki, J. C. Kieffer, R. Morandotti, M. Reid, and F. A. Hegmann, “Terahertz pulse induced intervalley scattering in photoexcited GaAs,” Opt. Express17(12), 9620–9629 (2009). [CrossRef] [PubMed]
  20. J. Hebling, M. C. Hoffmann, H. Y. Hwang, K.-L. Yeh, and K. A. Nelson, “Observation of nonequilibrium carrier distribution in Ge, Si, and GaAs by terahertz-pump terahertz probe measurements,” Phys. Rev. B81(3), 035201 (2010). [CrossRef]
  21. M. C. Hoffmann and D. Turchinovich, “Semiconductor saturable absorbers for ultrafast terahertz signals,” Appl. Phys. Lett.96(15), 151110 (2010). [CrossRef]
  22. G. Sharma, L. Razzari, F. H. Su, F. Blanchard, A. Ayesheshim, T. L. Cocker, L. V. Titova, H. C. Bandulet, T. Ozaki, J. C. Kieffer, R. Morandotti, M. Reid, and F. A. Hegmann, “Time-resolved terahertz spectroscopy of free carrier nonlinear dynamics in semiconductors,” IEEE Photon. J.2(4), 578–592 (2010). [CrossRef]
  23. M. C. Nuss and J. Orenstein, Millimeter and Submillimeter Wave Spectroscopy of Solids (Springer-Verlag, Berlin, 1998).
  24. H. G. Roskos, M. D. Thomson, M. Kreß, and T. Löffler, “Broadband THz emission from gas plasmas induced by femtosecond optical pulses: From fundamentals to applications,” Laser Photon. Rev.1(4), 349–368 (2007). [CrossRef]
  25. F. A. Hegmann and K. P. Lui, “Optical pump-terahertz probe investigation of carrier relaxation in radiation-damaged silicon-on-sapphire,” Proc. SPIE4643, 31–41 (2002). [CrossRef]
  26. P. N. Saeta, J. F. Federici, B. I. Greene, and D. R. Dykaar, “Intervalley scattering in GaAs and InP probed by pulsed far-infrared transmission spectroscopy,” Appl. Phys. Lett.60(12), 1477–1479 (1992). [CrossRef]
  27. M. Lundstrom, Fundamentals of carrier transport (Cambridge University Press, Cambridge, 2000).
  28. W. Walukiewicz, L. Lagowski, L. Jastrzebski, M. Lichtensteiger, and H. C. Gatos, “Electron mobility and free-carrier absorption in GaAs: Determination of the compensation ratio,” J. Appl. Phys.50(2), 899–908 (1979). [CrossRef]
  29. K. Blotekjaer, “Transport equations for electrons in two-valley semiconductors,” IEEE Trans. Electron. Dev.17(1), 38–47 (1970). [CrossRef]
  30. A. M. Anile and S. D. Hern, “Two-valley hydrodynamical models for electron transport in gallium arsenide: Simulation of Gunn oscillations,” VLSI Des.15(4), 681–693 (2002). [CrossRef]
  31. M. Grundmann, The Physics of Semiconductors (Springer-Verlag, 2006).
  32. D. G. Cooke, “Time-resolved terahertz spectroscopy of bulk and nanoscale semiconductors,” PhD dissertation, (Department of Physics, University of Alberta, 2007).
  33. J. F. Young, P. J. Kelly, N. L. Henry, and M. W. C. Dharma-Wardana, “Carrier density dependence of hot-electron scattering rates in quasi-equilibrium electron-hole plasmas,” Solid State Commun.78(5), 343–346 (1991). [CrossRef]
  34. M. C. Beard, G. M. Turner, and C. A. Schmuttenmaer, “Transient photoconductivity in GaAs as measured by time-resolved terahertz spectroscopy,” Phys. Rev. B62(23), 15764–15777 (2000). [CrossRef]
  35. D. M. Caughey and R. E. Thomas, “Carrier mobilities in silicon empirically related to doping and field,” Proc. IEEE55(12), 2192–2193 (1967). [CrossRef]
  36. M. C. Nuss, D. H. Auston, and F. Capasso, “Direct subpicosecond measurement of carrier mobility of photoexcited electrons in gallium arsenide,” Phys. Rev. Lett.58(22), 2355–2358 (1987). [CrossRef] [PubMed]
  37. D. G. Cooke, F. A. Hegmann, E. C. Young, and T. Tiedje, “Electron mobility in dilute GaAs bismide and nitride alloys measured by time-resolved terahertz spectroscopy,” Appl. Phys. Lett.89(12), 122103 (2006). [CrossRef]

Cited By

Alert me when this paper is cited

OSA is able to provide readers links to articles that cite this paper by participating in CrossRef's Cited-By Linking service. CrossRef includes content from more than 3000 publishers and societies. In addition to listing OSA journal articles that cite this paper, citing articles from other participating publishers will also be listed.


Fig. 1 Fig. 2 Fig. 3
Fig. 4

« Previous Article  |  Next Article »

OSA is a member of CrossRef.

CrossCheck Deposited