Modulation characteristics of high speed (f-3 dB=20 GHz) tunneling injection InP/InGaAsP 1.55 μm ridge waveguide lasers extracted from optical and electrical measurements

High-performance multiquantum-well 1.55 μm InP-based tunneling injection lasers are fabricated using a conventional single mode ridge waveguide fabrication process and characterized. The lasers consist of an eight quantum-well strain-compensated gain region and a 30-Å InP tunneling barrier. The bandwidth of these lasers is measured to be 20 GHz with a damping limited bandwidth extracted from the K-factor (determined from optical modulation measurements) of 26 GHz. To our knowledge, this is the highest measured bandwidth recorded for an InP-based simple ridge waveguide structure. The differential gain is measured to be as high as 1×10^-15 cm², with a measured gain compression coefficient ε of 5×10^-17 cm³. It is shown that the K-factor can also be extracted solely from measurements of the small signal electrical impedance. The carrier escape time τ_esc is determined to be 0.5 ns, independent of bias. This high frequency performance is achieved with a very simple device structure at room temperature under constant drive currents