Dynamic behaviors of the high-speed oxide-confined vertical-cavity surface-emitting laser based on an electro-optical-thermal model

An electro-optical-thermal (E-O-T) model for the high-speed 850-nm oxide-confined VCSEL is presented. The static performance, small- and large-signal modulation responses of the VCSEL are calculated based on the E-O-T model. The measured power-current-voltage (<i>P</i>-<i>I</i>-<i>V</i>) curves, small-signal modulation responses, and eye diagrams at 25 °C and 85 °C agree well with the simulated results. It is also found that carrier unpinning occurs due to the thermal effects. At 85 °C, the fraction of the current for the stimulated emission is reduced compared with that at 25 °C. The total internal capacitance and junction impedance strongly influence the modulation bandwidth of the VCSEL. Furthermore, the influences of the thermal resistance, carrier transport, material gain, and cavity loss on the <i>P</i>-<i>I</i>-<i>V</i> characteristics, small-signal modulation response, and eye diagrams are investigated.