Black Phosphorus Based All-Optical-Signal-Processing: Toward High Performances and Enhanced Stability

Two-dimensional (2D) black phosphorus (BP) shows thickness dependent direct energy band-gaps in association with strong light-matter interaction and broadband optical response, rendering it with promising optoelectronic advantages particularly at the telecommunication band. However, intrinsic BP suffers from irreversible oxidization, restricting its competences toward real device applications. As one potential of 2D materials, all-optical signal processing sensitively depends on the strength of light–matter interaction. BP can be utilized as a novel optical medium. Herein, few-layer BP is synthesized with metal-ion-modification against oxidation and degradation, and then the feasibility of BP-coated microfiber as an optical Kerr switcher and a four-wave-mixing-based wavelength converter is demonstrated. The wavelength-tuning, long-term stability, wide-band RF frequency, and time-repeating measurements confirm that this optical device can operate as a broadband all-optical processor. It is further anticipated that metal-ion-modified BP might provide a new effective option for photonic applications toward high performances and enhanced stability.