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Updated: Oct 30, 2025

Design, Fabrication, and Experimental Characterization of Plasmonic Photoconductive Terahertz Emitters
Published on: July 8, 2013
Terahertz Pulse Emission from Semiconductor Heterostructures Caused by Ballistic Photocurrents
Vitaly Leonidovich Malevich1,2, Pavel Aliaksandravich Ziaziulia3, Ričardas Norkus4
1Stepanov Institute of Physics, National Academy of Science, Nezavisimosti Avenue 68, 220072 Minsk, Belarus.
Abstract:
Terahertz radiation pulses emitted after exciting semiconductor heterostructures by femtosecond optical pulses were used to determine the electron energy band offsets between different constituent materials. It has been shown that when the photon energy is sufficient enough to excite electrons in the narrower bandgap layer with an energy greater than the conduction band offset, the terahertz pulse changes its polarity. Theoretical analysis performed both analytically and by numerical Monte Carlo simulation has shown that the polarity inversion is caused by the electrons that are excited in the narrow bandgap layer with energies sufficient to surmount the band offset with the wide bandgap substrate. This effect is used to evaluate the energy band offsets in GaInAs/InP and GaInAsBi/InP heterostructures.
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