Ultrafast Cross-Switching of Long Wavelength Near-Infrared Pulses in Dual-Core Soft Glass Fibers for Time Gating of Spectroscopy Signals

One of the ways to realize all-optical switching of ultrafast signals is via nonlinear interaction in dual-core fibers (DCF). A novel technique leading to effective switching of 1.55 μm femtosecond (fs) pulses based on their cross-interaction with 1.03 μm control pulses in DCFs has been demonstrated previously [1]. We developed a second-generation DCF, which is a highly nonlinear, high-index contrast fiber made of thermally matched soft glasses PBG-08 (lead silicate) and UV-710 (borosilicate), comprising five dual-core units as shown in Fig. 1a [2]. The dual-wavelength cross-switching principle utilizes the nonlinear balancing of the dual-core asymmetry by the control pulse, which leads to the switching of the signal pulse when the fiber length is close to the coupling length [2]. In this contribution, we present notable improvements of the dual-wavelength switching approach in multiple key aspects, advancing its feasibility for single-shot time-resolved spectroscopy tasks.