Memory effect in two-dimensional TMD/phyllosilicate-based heterostructures

• Grant number: 25/02343-0
• Support Opportunities: Regular Research Grants
• Start date: November 01, 2025
• End date: October 31, 2028
• Field of knowledge: Physical Sciences and Mathematics - Physics - Condensed Matter Physics
• Principal Investigator: Marcio Daldin Teodoro
• Grantee: Marcio Daldin Teodoro
• Host Institution: Centro de Ciências Exatas e de Tecnologia (CCET). Universidade Federal de São Carlos (UFSCAR). São Carlos , SP, Brazil
• City of the host institution: São Carlos
• Associated researchers: Alisson Ronieri Cadore ; Frederico Barros de Sousa
• Associated scholarship(s): 25/24550-7 - Optical memory development in bidimensional heterosctructures, BP.DR

Abstract

With the advancements in the studies of two-dimensional (2D) materials, there is a continuous effort to investigate insulators for use as substrates in van der Waals heterostructures. For this purpose, atomically flat materials with a wide bandgap and low impurity concentration, such as hexagonal boron nitride (hBN), stand out for providing an inert environment and thus enhancing the properties of the materials supported on them. On the other hand, the interest in fabricating 2D heterostructures sometimes lies in modulating the properties of each material through the interaction between distinct layers, which is limited at interfaces with hBN. Therefore, alternative insulators have been investigated to explore new functionalities in 2D materials. Among these insulators is clinochlore, an atomically flat material belonging to the phyllosilicate group. The presence of defects and impurities in its structure, resulting from its natural occurrence, interacts with and induces new phenomena in 2D semiconductors, as exemplified by the recently reported optical memory effect in a MoSe¿/Clinochlore device. In this device, coined as a mem-emitter, the photoluminescence emissions of the MoSe¿ monolayer are affected by transient processes of internal variables within the clinochlore. Consequently, the modulation of light emission in this device by an external electric field exhibits memory effects governed by the temporal dynamics of the substrate's internal processes. This effect highlights the ability of natural insulators to induce new optoelectronic phenomena in 2D semiconductors, emphasizing the still largely unexplored and poorly understood potential of these materials. In this context, this project proposes the study of natural insulators and their heterostructures with MoSe¿ through optoelectronic, magneto-optoelectronic, and time-resolved optoelectronic measurements. With this, we aim to significantly contribute to a better understanding of the optical properties of phyllosilicates. Additionally, we seek to understand how the transient processes of these insulators interact with magneto-optical responses, second-harmonic generation, and recombination dynamics in monolayers and bilayers of MoSe¿. Thus, we intend to build a complete framework for understanding and developing optical memories based on synthetic and natural 2D materials. (AU)