Probing Optical Multi-Level Memory Effects in Single Core-Shell Quantum Dots and Application Through 2D-0D Hybrid...

Area of Science:

• Materials Science
• Optoelectronics
• Quantum Computing

Background:

• Developing multi-level memory (MM) devices for multinary arithmetic computers faces challenges in achieving low-power, ultra-high-speed operation.
• Optical communication offers a solution for efficient data transfer between arithmetic and storage devices.

Purpose of the Study:

• To demonstrate a 2D-0D hybrid optical multi-level memory (OMM) device utilizing quantum dots (QDs) with a floating gate architecture.
• To investigate the mechanism of the OMM effect and explore optically controlled memory operations.

Main Methods:

• Replication of a floating gate architecture using CdSe/ZnS type-I core/shell quantum dots (QDs).
• Operation of the OMM device using laser pulses for programming and voltage pulses for resetting.
• Analysis of electron transfer mechanisms via energy band alignment between MoS2 and CdSe.

Main Results:

• Demonstration of an OMM device exhibiting multi-level memory characteristics through laser-induced optically trapped currents.
• Confirmation that charge transfer is hindered by a double ZnS shell between adjacent QDs.
• Each laser pulse independently induced MM characteristics in the 2D-0D hybrid architecture.

Conclusions:

• Proposal of a multi-level memory (MM) inverter for programming and erasing solely via laser pulses.
• Evaluation of the feasibility of a fully optically-controlled intelligent system using OMM inverters for pattern recognition.