2.2 micron, uncooled, InGaAs photodiodes, and balanced photoreceivers up to 25 GHz bandwidth

Abstract

We report lattice-mismatched, uncooled, 2.2 µm wavelength cutoff, InGaAs photodiodes and balanced photoreceivers with bandwidth up to 25 GHz. The responsivity at 2.05 µm is 1.2 A/W, and the 1 dB compression, optical current handling of these photodiodes is 10 mA at 7 V reverse bias. Such high current handling capacity allows these photodiodes to operate with a higher DC local oscillator (LO) power, thus, allowing more coherent gain and shot noise limited operation. The impulse response of these devices show rise time / fall time of ~15 ps, and full width half maximum of ~20 ps.