High-speed VCSELs for short reach communication

We present the design of a high-speed 850 nm multimode vertical cavity surface-emitting laser (VCSEL) and demonstrate record performance in terms of small signal modulation bandwidth (23 GHz) and error-free operation at high bit rates (40 Gb s−1). The large bandwidth was enabled by an active region design for large differential gain and small gain compression, a low reflectivity top mirror for photon lifetime reduction and multiple oxide layers for a reduction of the capacitance. Error-free operation at 40 Gb s−1 was achieved in a back-to-back configuration with less than 0 dBm of received optical power