A Black Phosphorus Carbide Infrared Phototransistor

Area of Science:

• Materials Science
• Optoelectronics
• Nanotechnology

Background:

• Broadband photodetectors are crucial for Internet-of-Things sensing.
• Existing 2D materials like graphene and black arsenic phosphorus have limitations in responsivity and response time.
• There is a need for advanced 2D materials with superior optoelectronic properties.

Purpose of the Study:

• To synthesize and characterize a novel 2D material, black phosphorus carbide (b-PC).
• To demonstrate a b-PC-based phototransistor for broadband detection.
• To evaluate the phototransistor's performance in terms of responsivity, response time, and detectivity.

Main Methods:

• Synthesis of black phosphorus carbide (b-PC) 2D material.
• Fabrication of a b-PC phototransistor device.
• Characterization of optoelectronic properties including responsivity, response time, and noise equivalent power at 2004 nm wavelength.
• Gating effect analysis for tunable device performance.

Main Results:

• Successful synthesis of b-PC with absorption spectrum up to 8000 nm.
• Demonstration of a b-PC phototransistor with tunable responsivity and response time.
• Achieved peak responsivity of 2163 A W⁻¹ and shot noise equivalent power of 1.3 fW Hz⁻¹/² at 2004 nm.
• Demonstrated a fast response time of 0.7 ns, tunable via gating.
• Outperformed existing 2D material photodetectors in responsivity and detectivity at low bias voltage (0.2 V).

Conclusions:

• Black phosphorus carbide (b-PC) is a promising 2D material for broadband photodetector applications.
• The b-PC phototransistor offers high performance, including tunable responsivity and fast response times.
• This material advancement paves the way for next-generation high-speed and sensitive optical sensing devices.