Tunnel injection In0.4Ga0.6As/GaAsIn0.4Ga0.6As/GaAs quantum dot lasers with 15 GHz modulation bandwidth at room temperature

Abstract

By utilizing tunnel injection of electrons, first demonstrated in quantum well lasers, we have measured enhanced small-signal modulation bandwidth, f−3dB,f−3dB, and reduced temperature sensitivity of the threshold current, characterized by T0,T0, in In0.4Ga0.6As/GaAsIn0.4Ga0.6As/GaAs self-organized quantum dot ridge waveguide lasers. Values of f−3dB = 15 GHzf−3dB=15GHz at 283 K and T0 = 237 KT0=237K for 318 ≥ T ≥ 278318⩾T⩾278 are measured in these devices. The differential gain at 283 K is dg/dn ≅ 8.5×10−14 cm2dg/dn≅8.5×10−14cm2 and the gain compression factor ϵ = 4.5×10−17 cm3.ϵ=4.5×10−17cm3. © 2002 American Institute of Physics.