InP/InGaAsP/InGaAs avalanche photodiodes with 70 GHz gain-bandwidth product

Abstract
A wide bandwidth (8 GHz) and a high gain-bandwidth product (70 GHz) have been achieved with InP/InGaAsP/InGaAs avalanche photodiodes (APD’s) grown by chemical beam epitaxy. These APD’s also exhibit low dark current (90% at λ=1.3 μm), and high avalanche gain (M0≂40).