Electrodynamics of plasma oscillations in semiconductor microdevices with two-dimensional electron channels

Electromagnetic theory of plasma oscillations in field-effect transistor with two-dimensional electron channel is presented. Two different key electromagnetic problems are considered. They are the problems of diffraction of the plane electromagnetic wave (i) on the slot in infinite perfectly conductive plane, which is bridged by 2D electron channel and (ii) on the perfectly conductive strip, which screens partially an infinite 2D electron sheet located at a given distance from the strip. New physics inherent in these problems is revealed.