Ultrahigh-performance and broadband photodetector from visible to shortwave infrared band based on GaAsSb nanowires

Novel compact multispectral photodetectors detect various wavelengths, enabling visible light (VIS) and short-wave infrared (SWIR) dual-band detection for target identification and imaging. Nevertheless, combining VIS and SWIR photodetectors for multispectral detection faces challenges due to structural design and integration complexities. To streamline integration hurdles, high-Sb composition large-diameter GaAsSb nanowire photodetectors were developed, minimizing recombination centers and boosting gain. These photodetectors exhibit a high response in the light range from VIS (400 nm) to SWIR (2000 nm), exhibiting an ultrasensitive rise time (τ_r) of ∼0.8 ms, ultrahigh responsivity (R) of ∼2.32 × 10⁵ A/W, and excellent detectivity (D*) of ∼9.10 × 10¹³ Jones in VIS (532 nm), and rapid τ_r of ∼6.5 ms, high R of ∼4.83 × 10³ A/W with D* of ∼6.43 × 10¹¹ Jones in SWIR (1300 nm), surpassing most previously reported III-V NW-based photodetectors. The simplified single GaAsSb NW photodetector significantly reduces the structural complexity and integration, achieving an ultrahigh-performance broadband optical response from the VIS to the SWIR region. The proposed broadband photodetector offers a potential approach for streamlining the integration of VIS/SWIR technologies and is expected to be applied in optical communication, monitoring, and imaging systems.