Plasma mechanism of terahertz photomixing in high-electron mobility transistor under interband photoexcitation

We show that modulated near-infrared radiation can generate terahertz plasma oscillations in the channel of a high-electron mobility transistor. This effect is associated with a temporarily periodic injection of the electrons photoexcited by modulated near-infrared radiation into the transistor channel. The excitation of the plasma oscillations has the resonant character. It results in the pertinent excitation of the electric current in the external circuit that can be used for generation of terahertz electromagnetic radiation.