Photorefractive power transfer from parallel laser diode amplifiers into a single output beam

Photorefractive BaTiO3:Ce was used to combine coherently a signal beam and two amplified pump beams at λ=678  nm. The master laser beam was split and then amplified in two semiconductor laser amplifiers with gain of as much as 6. The amplifiers were made from quantum-well laser chips by use of antireflection coating. 40% of the power could be transferred to the signal beam without transferring the phase distortions of the pump beams.