Origin of large variations of current on/off ratio and switching voltage in atomically thin memristors: an exascale ab initio transport study
Year: 2025
Type: article
Abstract: Nonvolatile resistive switching in two-dimensional monolayers opens a new avenue for high-density memory/computing devices. However, questions remain as to why the current on/off ratio and switching voltage vary significantly among different devices. Here, we simulate electronic transport of large systems consisting of a h-BN monolayer sandwiched by gold electrodes, enabled by an implementation of the nonequilibrium Green’s function method in the exascale density functional theory (DFT) code: Real-space MultiGrid. Systematic calculations reveal that the wide range of on/off ratios is due to variations in interface distances between the electrode and h-BN that significantly modulate their wavefunction overlap. In addition, DFT calculations demonstrate that the energy barrier of a gold atom dissociating from the electrode to h-BN increases dramatically with the interface distance, thereby explaining the strong dependence of the switching voltage on distance. Our work demonstrates the significance of interface distance in governing the current on/off ratio and switching voltage.
Language: English
Subfield: Electrical and Electronic Engineering
Field: Engineering
Domain: Physical Sciences
Open Access status: gold
Estimated APC paid: $3,405
Awards: G121915436, G122673668, G1286236842, G1645119126, G1677143136, G1863003419, G203625172, G2144044613, G2411683797, G2988778103, G3083819904, G419881185, G42916606, G4423657506, G4501827968, G498139845, G5076365615, G5261056217, G5455815247, G5892109311, G660579501, G6720549874, G675320460, G7651947074, ECCS-EPSRC: Overcoming the Endurance Challenge in Energy-Efficient Atomic Memristors for AI and 6G Applications, G8269158468, G8876996369, G8906985441, G969889393
OpenAlex ID: W4416182902