Black Arsenic–Phosphorus Nanosheets for Highly Responsive Photodetection and Dual-Wavelength Ultrafast Pulse Generation at Telecommunication Bands

• Published in: ACS applied materials & interfaces Vol. 14; no. 46; pp. 52270 - 52278
• Main Authors: Bao, Xiaozhi, Zhuo, Linqing, Dong, Weikang, Guo, Junpo, Wang, Gang, Wang, Bingzhe, Wei, Qi, Huang, Zongyu, Li, Jianding, Shen, Jingjun, Yu, Jianhui, Nie, Zhaogang, Ren, Wencai, Liu, Guanyu, Xing, Guichuan, Shao, Huaiyu
• Format: Journal Article
• Language: English
• Published: American Chemical Society 23.11.2022
• Subjects: Functional Nanostructured Materials (including low-D carbon); mode locking; b-AsP; nonlinear optical properties; dual wavelength; photodetector
• ISSN: 1944-8244; 1944-8252
• DOI: 10.1021/acsami.2c10857

Black arsenic–phosphorus (b-AsP), an alloy containing black phosphorus and arsenic in the form of b-As x P1–x , has a broadly tunable band gap changing with the chemical ratios of As and P. Although mid-infrared photodetectors and mode-locked or Q-switched pulse lasers based on b-AsP (mostly b-As0.83P0.17) are investigated, the potential of this family of materials for near-infrared photonic and optoelectronic applications at telecommunication bands is not fully explored. Here, we have verified a multifunctional fiber device based on b-As0.4P0.6 nanosheets for highly responsive photodetection and dual-wavelength ultrafast pulse generation at around 1550 nm. The fiber laser with a saturable absorber (SA) based on b-As0.4P0.6 nanosheets can output dual-wavelength mode-locking pulses with a larger bandwidth and spectral separation than those based on other two-dimensional (2D) materials. Remarkably, it is found that the b-As0.4P0.6-based photodetector can achieve a high responsivity of 10,200 A/W at 1550 nm and a peak responsivity of 2.29 × 105 A/W at 980 nm. Our work suggests that b-As0.4P0.6 shows great potential in ultrafast photonics, dual-comb spectroscopy, and infrared signal detection.