Multispectral Integrated Black Arsenene Phototransistors for High-Resolution Imaging and Enhanced Secure...

Area of Science:

• Materials Science
• Optoelectronics
• Nanotechnology

Background:

• Growing demand for broadband, room-temperature infrared, and terahertz (THz) detectors for applications in telecommunications, security, and medical diagnostics.
• Limitations of current photodetectors, including high dark currents and the need for cryogenic cooling, hinder low-energy photon detection.

Purpose of the Study:

• Introduce a high-performance, ultrabroadband photodetector operating at room temperature.
• Utilize two-dimensional black arsenene (b-As) nanosheets for enhanced photodetector performance across multiple spectral ranges.

Main Methods:

• Fabrication of a room-temperature photodetector using two-dimensional black arsenene (b-As) nanosheets.
• Integration of antenna-coupled field-effect transistors with asymmetric antennas for plasma-wave rectification in the terahertz range.
• Characterization of device responsivity across visible, near-infrared, and THz spectral ranges.

Main Results:

• Demonstrated ultrabroadband responsivity from visible to THz frequencies.
• Achieved high responsivities: 91.6 A/W at 520 nm, 6.3 A/W at 1550 nm, and 7.8 V/W at 0.27 THz.
• Observed a voltage-dependent bipolar response in THz detection due to plasma-wave rectification.

Conclusions:

• The developed black arsenene photodetector offers high performance at room temperature across a wide spectrum.
• The device enables secure terahertz communication through complex logic operations, data encryption, and signal processing.
• This technology addresses key limitations of existing photodetectors, paving the way for advanced applications.