Direct frequency modulation of vapor-phase-transported distributed- feedback semiconductor lasers.
01 January 1986
The frequency modulation due to injection current modulation of vapor-phase-transported distributed-feedback (VPT-DFP) semiconductor lasers is measured as a function of modulation frequency from 10kHz to 1GHz. A large frequency modulation response of 350MHz/mA is obtained for the modulation frequency range of 10 to 1,000MHz. Demodulation of optical FSK transmission at 560Mb/s is demonstrated, indication that frequency modulation due to thermal modulation does not pose a significant limitation at this bit rate or higher. The large FM response together with modulation bandwidths up to 8GHz make the VPT-DFB laser an attractive source for high bit rate optical FSK transmission.