Abstract

The output frequency of a semiconductor laser is primarily determined by its operating temperature and injection current. A straightforward method of frequency stabilization can thus be based upon controlling these two parameters. In practice, though, it is quite impossible to measure the temperature of the active region of the laser diode accurately with any external sensor. The carrier densities which determine the electric resistance of the diode laser are, however, highly sensitive to the laser temperature. Therefore, with the injection current held constant the voltage across the junction gives a good measure of this temperature. Stabilization of the laser frequency can then simply be based on keeping the voltage and the current of the laser constant^[14].

© 1992 IQEC