Thermal contribution to wavelength switching characteristics of widely tunable lasers

Thermal effects on wavelength switching dynamics are investigated for a wideband laser. For frequency shift keying (FSK) applications it has been shown that the laser phase current must be switched every 30 ns or in other words modulated at over 35 MHz, to achieve full range frequency dither. Alternatively FSK as low as 5 MHz is possible with a 10% loss of frequency excursion. In this paper, thermal effects on the FSK modulation and wavelength switching dynamics are investigated for a grating-assisted co-directional coupler with sampled grating reflector (GCSR) laser with the phase section.