Optical response of the GaAs MESFET at microwave frequencies and applications

The authors consider the MESFET as an optical port on MMICs (monolithic microwave integrated circuits). It is shown quantitatively how better optical coupling improves the photoresponse of the MESFET. It is pointed out that by modest redesign its frequency response can be significantly extended up to 10 GHz. How these can be converted to better optical control of MMIC circuits is demonstrated. A direct optical injection locking of a MESFET oscillator was performed. The measured optical injection locking bandwidth was 43.8 MHz.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">></ETX>