Generation of Optical Microwave Based on Integration of Parallel DFB Laser and Y-branch Coupler

A new device of two parallel DFB lasers integrated monolithically with Y-branch waveguide coupler was fabricated. There was little difference between the frequencies of the two laser modes because of the respective work condition. Optical microwave signal was generated when frequency beating of the two laser modes was happened in the Y-branch waveguide coupler. Continuous tuning optical microwave signal from 13 GHz to 42 GHz were realized when adjusting independently the driving currents injected into the two DFB lasers.