Giant Pulse at 2 μm in Polarization Maintaining Silica Step-Index Fiber

Since the two last decades, ultrashort pulses operating around 2 μm are useful for a commercial and scientific applications, e.g. mid-infrared supercontinuum generation [1] or pumping of optical parametric oscillators. To obtain such pulses, mode-locked fiber lasers based on Thulium or Holmium doped fiber gains are usually used. An alternative consists on a nonlinear approach `the Raman soliton self-frequency shift' (SSFS) [2]. It leads to a red shift of the signal allowing then to access to 2 pm. Recently, an Erbium-doped fiber laser coupled with a photonic crystal fiber (PCF) and a dispersion compensating fiber has allowed to generate sub-100 fs pulses tunable from 1700 nm to 2100 nm [3]. Here, we demonstrate experimentally the formation of a giant pulse based on the interaction between two Raman solitons in PM silica step-index fiber.