Thermal and electrical sensitivities of optical devices under microwave intensity modulation

Thermal and electrical sensitivities of an optical device (directly modulated single-mode GaAlAs laser diode SL-620) under microwave intensity modulation is analyzed on the basis of a small-signal nonlinear model. Temperature-dependent device parameters are employed throughout the rate equations where the effect of gain compression as well as the nonlinear gain are considered. The steady-state components are separated, and the AC-components are employed to obtain a normalized transfer function relating to the photonic energy output and the electric energy input with device parameters and the operating microwave frequency. Simple quadratic correlations are derived for four basic relevant variables: resonance peak, resonance frequency, gain cross-over frequency and 3-dB bandwidth