Proceedings Article | 1 May 2017
Proc. SPIE. 10192, Laser Technology for Defense and Security XIII
KEYWORDS: Wave propagation, Structured optical fibers, Mid-IR, Visible radiation, Supercontinuum generation, Fiber lasers, Glasses, Defense and security, Transparency, Silica, Chalcogenides, Femtosecond phenomena
Supercontinuum has great potential in defense applications due to its wide spectrum, high coherence and high brightness, and it has attracted more and more attention across the world especially in the visible and mid-infrared region like 3-5μm which is the atmospheric transparency window. Higher power, wider spectrum, and better spectrum flatness will be the dominant pursuit for the future development of supercontinuum. Currently silica based fiber are the dominant host for visible to near-infrared supercontinuum generation, and soft glass like fluoride fiber, chalcogenide fiber and tellurite fiber are widely used for mid-infrared supercontinuum generation due to their lower loss in the mid-infrared region. In this paper, the generalized non-linear Schrödinger equation is used to simulate the visible to mid-infrared supercontinuum generation in a tellurite fiber. A femtosecond laser at 1064 nm worked as the pump source. 1.5 μm and 2 μm lasers are generally first pump candidates to generate mid-infrared supercontinuum in tellurite glass because the zero-dispersion wavelength of the tellurite glasses is around 2.15 μm. However, 1064 nm laser has more advantages in application in terms of cost, structure, and power scaling, so it is meaningful to investigate whether 1064 nm laser can pump tellurite fiber to generate supercontinuum with wide bandwidth. The simulation results show that 500 nm-5000 nm supercontinuum can be generated in a tellurite fiber with less than 10 kW peak power for the pump laser, and the length of the tellurite fiber is only several millimeter. The simulation results provide important guidance for future supercontinuum development.