@misc{10481/97101,
year = {2024},
month = {10},
url = {https://hdl.handle.net/10481/97101},
abstract = {Two-dimensional materials, in particular transition
metal dichalcogenides (TMDs), have attracted a nascent interest in
the implementation of memristive architectures. In addition to
being functionally similar to synapses, their nanoscale footprint
promises to achieve the high density of a biological neural network
in the context of neuromorphic computing. However, in order to
advance from the current exploratory phase and reach reliable and
sound memristive performances, an understanding of the underlying
physical mechanisms in TMD memristors seems imperative.
Despite the distinctive transport medium inherent to multilayer
TMDs, the memristance is routinely attributed to defects or metal
atoms present in the system, with their precise contribution
remaining elusive. Specifically, the role of intrinsic point defects in the formation of conductive channels, although shown for
monolayer TMDs, is not conclusively studied for multilayer samples. In this work, using density functional theory (DFT) and
nonequilibrium Green’s function (NEGF) formalism, a systematic study is carried out to analyze the impact that defects and metal
atoms produce on the out-of-plane conductivity of multilayer TMDs. MoS2, a representative of the 2H structural configuration, and
PtS2, a representative of the 1T structure, the most common crystal arrangements among TMDs, are used for this analysis. It is
found that the intrinsic sulfur vacancies, which are the dominant defects present in both TMDs, appear to be insufficient in causing
resistive switching on the application of an external bias. The claim that the intrinsic point defects on their own can realize a valence
change memory-type device by providing a controllable conductive channel through the van der Waals structure seems, according to
our study, improbable. The presence of metallic atoms is demonstrated to be essential to trigger the memristive mechanism,
emphasizing the proper choice of a metal electrode as being critical in the fabrication and optimization of memristors using TMDs.},
organization = {Project ENERGIZE under
grant agreement No. 101194458 funded by the European
Union’s Horizon Europe},
organization = {Spanish Government through the projects PID2020-
116518GB-I00 funded by MCIN/AEI/10.13039/
501100011033 and CNS2023-143727 RECAMBIO funded
by MCIN/AEI/10.13039/501100011033 and the European
Union NextGeneration EU/PRTR and by Consejería de
Universidad, Investigación e Innovación de la Junta de
Andalucía, through the P21_00149 ENERGHENE research
project},
organization = {European
Union’s Horizon 2020 research and innovation programme
under the Marie Sklodowska-Curie grant agreement No.
101032701},
organization = {R+D+i
project A-ING-253-UGR23 AMBITIONS cofinanced by
Consejería de Universidad, Investigación e Innovación and
the European Union, under the FEDER Andalucía 2021-2027},
organization = {University of Granada/
CBUA},
publisher = {ACS Publications},
keywords = {neuromorphic computing},
keywords = {synapse},
keywords = {memristor},
title = {Role of Point Defects and Ion Intercalation in Two-Dimensional Multilayer Transition Metal Dichalcogenide Memristors},
doi = {10.1021/acsanm.4c04769},
author = {Dineshkumar Ganeriwala, Mohit and Toral-Lopez, Alejandro and Calaforra-Ayuso, Estela and Pasadas Cantos, Francisco and Ruiz, Francisco G. and Marin, Enrique G. and Godoy Medina, Andrés},
}