Wavelength Locking and Determination in Tunable Lasers by Gain Voltage Measurement

In this paper we demonstrate the feasibility of low-cost lasers with an integrated wavelength locker and wavelength meter. We use a reflection at the polymer chip to single mode fiber butt coupling point to establish optical feedback outside the laser cavity to make the gain voltage wavelength dependent. With this signal we can keep the alignment of the lasing mode and the Bragg grating optimal and can determine the absolute wavelength of the emitted wavelength without additional hardware.