All-inorganic perovskite quantum dot light-emitting memories

Area of Science:

• Materials Science
• Nanotechnology
• Optoelectronics

Background:

• Ionic motion in cesium lead bromide (CsPbBr₃) perovskite quantum dots (QDs) significantly impacts electro-optical properties and device performance.
• Existing optoelectronic devices often lack multifunctionality and speed required for advanced applications.

Purpose of the Study:

• To investigate the dynamic switching of CsPbBr₃ QD devices between resistive random-access memory (RRAM) and light-emitting electrochemical cell (LEC) functionalities.
• To develop a fast, all-perovskite light-emitting memory (LEM) device for integrated data storage and optical readout.

Main Methods:

• Fabrication and characterization of single Ag/CsPbBr₃/ITO devices.
• Modulation of bias polarity to switch device functionality between RRAM and LEC modes on a sub-millisecond timescale.
• Integration of two identical devices in series to create a light-emitting memory (LEM) device operating at 5 kHz.

Main Results:

• Demonstrated reversible switching between RRAM and LEC functionalities in a single CsPbBr₃ QD device by altering bias polarity.
• Achieved the first realization of a fast, all-perovskite light-emitting memory (LEM) device operating at 5 kHz.
• Showcased parallel electrical data reading (RRAM) and non-contact optical data reading (LEC) with real-time perception of digital status via emission color.

Conclusions:

• Field-induced ionic motions in CsPbBr₃ QDs enable versatile device functionalities.
• The developed all-perovskite LEM offers a novel platform for high-speed, integrated optoelectronic memory.
• This work paves the way for advanced all-inorganic perovskite optoelectronic technologies.