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arXiv · 0812.4754

Impact ionization in InSb probed by THz-pump THz-probe spectroscopy

Matthias C. Hoffmann·Janos Hebling·Harold Y. Hwang·Ka-Lo Yeh·Keith A. Nelson
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Abstract

Picosecond carrier dynamics in indium antimonide (InSb) following excitation by below-bandgap broadband far infrared radiation were investigated at 200 K and 80 K. Using a novel THz-pump/THz-probe scheme with pump THz fields of 100 kV/cm and an intensity of 100 MW/cm^2, we observed carrier heating and impact ionization. The number of carriers produced exceeds 10^16 cm-3, corresponding to a change in carrier density Delta N/N of 700% at 80K. The onset of a well defined absorption peak at 1.2 THz is an indication of changes in LO and LA phonon populations due to cooling of the hot electrons.

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Matthias C. Hoffmann, Janos Hebling, Harold Y. Hwang, Ka-Lo Yeh, Keith A. Nelson. 2008-12-29. Impact ionization in InSb probed by THz-pump THz-probe spectroscopy. https://doi.org/10.1103/physrevb.79.161201

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