Multilevel Optical Memory with High Responsivity Based on Scalable Graphene/2D Perovskite Heterostructures

Area of Science:

• Materials Science
• Optoelectronics
• Nanotechnology

Background:

• Scalable optoelectronic memory is essential for advanced computing, including neuromorphic systems.
• Current devices face challenges in integration and performance for next-generation applications.

Purpose of the Study:

• To present a novel photoinduced charge-trapping memory (PCTM) device.
• To demonstrate its dual functionality for photodetection and nonvolatile optical memory.
• To highlight its potential for scalable, low-energy computing applications.

Main Methods:

• Fabrication of a heterostructure device using CVD-grown graphene and solution-processed 2D perovskite (butylammonium lead iodide).
• Characterization of device performance under varying illumination intensities.
• Analysis of charge trapping mechanisms and their effect on device functionality.

Main Results:

• The PCTM device exhibits dual functionality: high-gain photodetector (responsivity up to 210 A/W) at high light intensities and nonvolatile optical memory at low intensities.
• The memory function shows multilevel current states with retention times exceeding 16 hours without applied voltage.
• Achieved significant photocurrent increases (over 51 μA per writing pulse) in multibit operation, a record for graphene-perovskite PCTMs.

Conclusions:

• The developed PCTM device offers a scalable, high-performance platform for optoelectronic memory.
• It effectively bridges photodetection and neuromorphic functionality, paving the way for advanced computing.
• The device's performance highlights its suitability for low-energy, multibit optical memory applications.