• August 25, 2026

  • ‍4:00 PM (CST): Spin-Dependent Transport and Resistive Switching in CuCrP2S6-Based Tunnel Junctions

    • Speaker: Dr. Khimananda Acharya (Department of Physics, South Dakota School of Mines and Technology)

    • Abstract

      • CuCrP2S6 (CCPS), a two-dimensional van der Waals multiferroic material, provides a promising

        platform for electrically tunable multistate non-volatile memory devices due to the coexistence of

        switchable ferroelectricity and layered magnetism. In this work, we performed a theoretical and

        experimental study of CCPS-based tunnel junctions. CCPS is a unique material with the

        coexistence of both ferroelectric (FE) and antiferroelectric (AFE) phases. First, an Au/CCPS/Au

        multiferroic tunnel junction is studied using density functional theory combined with

        nonequilibrium Green’s-function calculations. The AFE phase exhibits nearly ideal spin filtering,

        giant tunneling magnetoresistance (TMR) of approximately 3100%, and tunneling

        electroresistance (TER) approaching 9500% for a 4-layer CCPS device, while polarization

        switching strongly modifies the spin-dependent transport characteristics through interfacial charge

        redistribution. Second, an asymmetric Au/CCPS/Graphene vertical architecture is developed using

        a dry-transfer method on pre-patterned electrodes, allowing fast fabrication while avoiding posttransfer lithographic steps that may introduce residues or damage. The resulting ferroelectric

        memristor exhibits electrically tunable resistive switching and a record-high tunneling

        electroresistance (TER) of ~2.2×105% for comparable CCPS thickness. Density functional theory

        (DFT) calculations show that the combined effect of Au/CCPS and CCPS/Graphene interfaces

        plays a major role in producing a large difference in the potential barrier between polarization

        states and provides insight into the microscopic origins of the resistive switching behavior for AuCCCPS/Graphene device. These findings establish CCPS-based heterostructures as a versatile

        platform for multifunctional spintronic and ferroelectric memory applications.