Switching-time limitation in tunable multisection lasers

The impact of the thermal transient on the frequency switching of multisection tunable lasers is studied. A simple thermal model is used to calculate the amplitude and time evolution of the frequency transient due to the thermal properties of both the laser chip and its mount. Transient time constants as large as 200 mu s for the laser chip and several hundred milliseconds for the diode mount are measured, limiting the applicability of these devices to systems where the frequency is switched at low rates. A method to compensate electrically for this transient by means of a passive net work is demonstrated.<
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