Terahertz emission from collapsing field domains during switching of a gallium arsenide bipolar transistor.

Phys Rev Lett

University of Oulu, Department of Electricity and Information Engineering, Electricity Laboratory, Oulu, FIN-90014, Finland.

Published: October 2007

Broadband pulsed THz emission with peak power in the sub-mW range has been observed experimentally during avalanche switching in a gallium arsenide bipolar junction transistor at room temperature, while significantly higher total generated power is predicted in simulations. The emission is attributed to very fast oscillations in the conductivity current across the switching channels, which appear as a result of temporal evolution of the field domains generated in highly dense electron-hole plasma. This plasma is formed in turn by powerful impact ionization in multiple field domains of ultrahigh amplitude.

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http://dx.doi.org/10.1103/PhysRevLett.99.176601DOI Listing

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