Broadband and ultrafast all-optical switching based on transition metal carbide

Ultrafast all-optical switches have attracted considerable attention for breaking through the speed limitation of electric devices. However, ultrafast and high-efficiency all-optical switches based on two-dimensional (2D) materials can be achieved due to their strong nonlinear optical response and ultrafast carrier dynamic. For this reason, we propose the pump-probe method to achieve an ultrafast optical switcher with a response time of 192 fs and a switching energy of 800 nJ by using transition metal carbide (Nb2C). The response time and switching energy are far smaller than that of the all-optical device based on the saturable absorption effect of 2D materials. It is believed that the Nb2C-based all-optical switch provides a novel idea to achieve a high-performance all-optical device and has the potential for application in high-speed photonics processing.