Mid-Ir Hcpcf Gas-Laser Emitting At 4.6 Mu M

Infrared laser sources emitting in the atmospheric transmission window (i.e. the wavelength range of 3–5 μΉ and 8–13 μΉ) are of interest in applications such as remote sensing, imaging and free-space communications [1]. Within this context, Inhibited Coupling Hollow Core Photonic Crystal Fibers (IC-HCPCF) [2] offer an interesting platform for gas laser sources, especially for those emitting in spectral ranges where silica-based solid core fiber lasers fail because of the large infrared (IR) absorption losses of the host materials. Indeed, the possibility of filling HCPCF with gases, and combining long gas-light interaction lengths with small modal areas opened new avenues for laser development and nonlinear optics [3]. Furthermore, IC-HCPCFs exhibit particularly weak optical overlap between the guided field and the glass cladding material (typically in the range 104–106) [4]. Consequently, material absorption losses play a minor role in the mid-IR in a few meter-long silica-based IC-HCPCF as demonstrated previously [5]. This suggests that the concept of hollow fiber gas laser (HOFGLAS), which was demonstrated in the visible with I 2 [6] and at 3 μm with C 2 H 2 pulsed [7] and CW [8], can be extended to longer wavelengths. Here, we report on an optically pumped gas-laser based on N 2 O-filled IC-HCPCF. The pulsed N2O HOFGLAS is pumped at 1.517 μm and emits at 4.6 μm with a photon conversion efficiency of 9% and a slope efficiency of 3%.