High-Speed Wideband Voltage-Controlled Oscillator via an Injection-Locked Laser

We demonstrate a microwave voltage-controlled oscillator able to synthesize a wide range of frequencies in the GHz regime based on an optically injected semiconductor laser. The ability to understand and experimentally characterize the entire injection-locking domain is crucial for the realization and optimization of such a device. This characterization facilitates the identification of steady-state bias conditions, which lead to microwave oscillations. More importantly, it also identifies a regime in which the oscillation frequency can be tuned solely by adjusting the optically injected power, a parameter, which can easily be changed on a nanosecond time scale. In this letter tuning from 6-16 GHz is demonstrated, while tuning rates of ~ 1 × 10
¹⁸
Hz/sec are achieved using a <; 1 V drive signal, resulting in a voltage-controlled oscillator with rapid tuning speed when compared with conventional, e.g. YIG-based, oscillators.