Indirect optically controlled pseudomorphic HEMT based MMIC oscillator

Abstract

For the first time an indirect optically controlled monolithic integrated oscillator was fabricated and examined experimentally. The oscillator was designed for a frequency of about 7 GHz. By illuminating a 60x60 μm2 photodiode by the light of a pigtailed laser diode (λ=840 nm), the free-running frequency of the oscillator was tunable in a range of more than 7 MHz. A locking range of more than 3 MHz was achieved. A phase shift in the output signal of nearly 180° has been observed.