High photon conversion efficiency continuous wave lasing in an optically pumped I_2 hollow fiber gas laser in the visible region

Continuous wave lasing in the visible spectral region from a molecular iodine-filled hollow core photonic crystal fiber is demonstrated. More than an order of magnitude improvement in photon conversion efficiency has been achieved compared to previous nonfiber-based geometries in this spectral region. The laser shows strong coupling of pump and laser polarization.