Popis: |
We present in this paper second-harmonic generation (SHG) results of narrow-linewidth continuous-wave 1064 nm fiber lasers in periodically-poled crystals. We particularly compare SHG efficiencies that can be obtained in PPLN with single-frequency linearly-polarized fiber lasers and with narrow linewidth longitudinally multimode linearly-polarized fiber lasers. Both infrared lasers can provide around 4.5W at 1064nm. Due to the high number of modes, sum-frequencies between modes enhance the efficiency of multimode SHG by a factor of roughly 2 compared to single-frequency, but green generated radiation suffers from important intensity noise. Conversely, single-frequency SHG is less efficient, but intensity noise is greatly improved. |