Ultrasensitive and broadband phototransistors with tellurium nanoribbon for polarized light detection

Ultrasensitive and broadband polarization photodetectors have attracted significant interest in the fields of imaging and encrypted communications for developing next-generation transparent electronic systems. High-mobility van der Waals p-type semiconductors are considered as promising materials. However, relatively few p-type 1D/2D phototransistors have high mobility and high detectivity. Here, we propose cryogenic ultrasensitive and broadband polarization photodetectors based on 1D Te nanoribbon (NR) phototransistors under low temperatures (20-300 K). Notably, the hole mobility of the Te NR transistor is as high as 1310 cm² V⁻¹ s⁻¹ for the hole at room temperature. The Te NR photodetector exhibits super-high photoresponse from the visible (532 nm) to near-infrared (1550 nm) band within the range of 20-300 K. Moreover, it achieves polarization-sensitive photodetection, with an anisotropy ratio of 7.8, responsivity of ∼1.3 × 10⁴ A/W, and detectivity of ∼10¹⁵ Jones at 20 K. The ultrasensitive detection, image sensing, secure information transmission, and communication optoelectronics are exhibited. Our results showcase a promising device concept with applications in the fields of optical communication, infrared imaging information encryption/transmission.