40.1-GHz sub-freezing 850-nm VCSEL: microwave extraction of cavity lifetimes and small-signal equivalent circuit modeling

Abstract

We present an 850-nm vertical-cavity surface-emitting laser (VCSEL) constructed for a wide operating temperature range from 25°C to −50°C sub-freezing temperature, demonstrating 40.1-GHz at −50°C. The optical spectra, junction temperature, and microwave equivalent circuit modeling of a sub-freezing 850-nm VCSEL between −50°C and 25°C are also discussed. Reduced optical losses, higher efficiencies, and shorter cavity lifetimes at sub-freezing temperatures are the leading causes of the improved laser output powers and bandwidths. The e–h recombination lifetime and the cavity photon lifetime are shortened to 113 and 4.1 ps, respectively. Could potentially supercharge VCSEL-based sub-freezing optical links for applications in frigid weather, quantum computing, sensing, aerospace, etc.