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arXiv · 0905.0278

Nonlinear ultrafast modulation of the optical absorption of few cycle terahertz pulses in n-doped semiconductors

L Razzari·F H Su·G Sharma·F Blanchard·A Ayesheshim·H-C Bandulet·R Morandotti·J-C Kieffer·T Ozaki·M Reid·F A Hegmann
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Abstract

We use an open-aperture Z-scan technique to show how intense few-cycle terahertz pulses can experience a nonlinear bleaching of absorption in an n-doped semiconductor due to terahertz-electric-field-driven intervalley scattering of electrons in the conduction band. Coherent detection of the transmitted terahertz pulse waveform also allows the nonlinear conductivity dynamics to be followed with sub-picosecond time resolution. Both the Z-scan and time-domain results are found to be in agreement with our theoretical analysis.

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L Razzari, F H Su, G Sharma, F Blanchard, A Ayesheshim, H-C Bandulet, R Morandotti, J-C Kieffer, T Ozaki, M Reid, F A Hegmann. 2009-05-03. Nonlinear ultrafast modulation of the optical absorption of few cycle terahertz pulses in n-doped semiconductors. https://doi.org/10.1103/physrevb.79.193204

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