Real-Time Demonstration of 600-Gb/s DP-64QAM Self-Homodyne Coherent Bi-Direction Transmission with Un-Cooled DFB Laser

We report first successful real-time self-homodyne coherent bi-direction transmission demonstration with 600-Gb/s DP-64QAM under un-cooled ~7-MHz linewidth DFB laser. A novel coherent receiver is proposed to achieve automatic stabilization against polarization fluctuations of received LO.