Proceedings Article | 7 January 2008
Proc. SPIE. 6824, Semiconductor Lasers and Applications III
KEYWORDS: Optical design, Data modeling, Modulation, Distortion, Semiconductor lasers, Optical simulations, Analog electronics, Intermodulation, Circuit switching, Device simulation
Accurate and rapid analyses and simulation of semiconductor laser performance, such as small-signal modulation
bandwidth, dynamic impedance and large-signal nonlinear distortion etc., are required for the optimal design of an
optical communication system. In this paper, by introducing a novel normalized transformation for rate equations of
semiconductor lasers, a compact rate-equation-based circuit model is presented and implemented in Agilent's advanced
design system. Furthermore, the model is enhanced by including the current-voltage characteristics, and can be directly
cascaded with extrinsic parasitic circuits for circuit- or system-level simulation. Thus, the model is applicable for optical
transmission system performance evaluation and network characterization in both time and frequency domains.
The steady-state and small-signal characteristics, such as current-photon density curve, current-voltage curve and input
impedance, are predicted by this model. Two important dynamic characteristics of second-order harmonic distortion and
two-tone third-order intermodulation products are simulated under different driving conditions. Fundamental sinusoidal
signals at 1 GHz and 2GHz with peak-to-peak modulation current of 11.2mA and 18mA are used to investigate
second-order harmonic distortion of semiconductor lasers. For the two-tone third-order intermodulation, two
equal-amplitude sinusoidal signals at 4 GHz and 4.04 GHz, each with peak-to-peak modulation current of 11.2 mA, are
used to examine the products at 3.96 and 4.08 GHz. The simulated results are compared to the published measurements
results. Experiments show that the measured results agree well with the published data.