Distributed balanced photodetectors for high-performance RF photonic systems

A novel velocity-matched distributed balanced photodetector operating at 1.3 and l.55p.tm wavelengths has been experimentally demonstrated. Distributed absorption and velocity matching ofthe optical and microwave signals are employed to achieve high saturation photocurrent. A common mode rejection ratio greater than 27 dB has been achieved over a wide range of photocurrents. More than 24dB suppression of the relative intensity noise of the laser source and EDFA added noise has been achieved in a broadband RF link experiment. Shot noise limited performance has been achieved with significant improvements in the signal-to-noise ratio.