Themed collection New memory paradigms: memristive phenomena and neuromorphic applications

Ilia Valov and Philip Bartlett introduce the Faraday Discussion volume on New memory paradigms: memristive phenomena and neuromorphic applications.

This article provides a brief introduction to the Faraday Discussion “New memory paradigms: memristive phenomena and neuromorphic applications” held in Aachen, Germany, 15–17 October 2018.

The Faraday Discussion on New memory paradigms: memristive phenomena and neuromorphic systems was held from October 15–17 on the campus of the Rheinisch-Westfälische Technische Hochschule Aachen University, or RWTH Aachen University, under the auspices of the Royal Society of Chemistry.

We demonstrate how the intrinsic analogue programmability of memristive devices can be exploited to perform spike-sorting on single devices.

We demonstrated a proton-based 3-terminal synapse device which shows symmetric conductance change characteristics. Using the optimized device, we successfully confirmed the improved classification accuracy of neural networks for on-chip training.

Chalcogenide-based, programmable metallization cells (PMC) cells have been characterized after exposure to increasing levels of absorbed dose (i.e., ionizing radiation exposure).

Nano-confined phase change memory cells based on pure Sb have been electrically characterized.

Molecular dynamics simulations provide insights into the priming effects in the crystallization of the phase change compound GeTe.

We report a detailed study of neuromorphic switching behaviour in inherently complex percolating networks of self-assembled metal nanoparticles.

We show direct evidence for interfacial redox reactions in memristive devices based on both valence change and electrochemical metallization mechanisms.

We compare SiO_x and HfO₂ ReRAM technologies with fixed C and Ti electrodes to understand the role played by the switching layer.

Operando photoelectron spectroscopy of memristive devices indicates a reversible shift of oxygen during biasing which proceeds even after device breakdown.

In this work, the ultimate switching speed limit of redox-based resistive switching devices is discussed. Based on a theoretical analysis of the underlying physical processes, it is derived that the switching speed is limited by the phonon frequency.

This paper presents rules based on the physical behaviour of the device to instantiate logic gates for further computation and a method of understanding the memristor’s operation as a type of non-linear, sequence-sensitive perceptron.

In situ measurements using XPS were performed on Pt/TiO₂/TiO_x/graphene structures to chemically address switching and hysteresis.

We present phase diagrams of binary oxides, Hf–O, Zr–O and Y–O, obtained by ab initio evolutionary simulations, in order to explore possible metastable crystalline suboxide structures which could be quenched during the electroforming processes within the conductive filaments in stoichiometric HfO₂, ZrO₂ and Y₂O₃ host materials, in resistive switching devices.

The design and fabrication of a 2D passive phase change memory matrix by non-aqueous electrodeposition of confined Ge–Sb–Te cells.

Atomic details of extended mixed dislocations in a SrTiO₃ bicrystal are studied using scanning transmission electron microscopy, electron energy loss spectroscopy, and energy dispersive X-ray spectroscopy techniques.

This paper explores the impact of device failures, NVM conductances that may contribute read current but which cannot be programmed, on DNN training and test accuracy.

We investigated the resistive switching mechanism between the high-resistance state (HRS) and the low-resistance state (LRS) of the GeTe–Sb₂Te₃ (GST) superlattice.

In this paper, we present a spiking neural network architecture that supports the use of non-ideal memristive devices as synaptic elements and propose mixed-signal analog-digital interfacing circuits to mitigate/exploit such non-idealities for neuromorphic computation.

This work addresses the methodology and implementation of a neuromorphic SNN system to compute the temporal information among neural spikes using ReRAM synapses capable of spike-timing dependent plasticity (STDP).

We report a study of the relationship between oxide microstructure at the scale of tens of nanometres and resistance switching behaviour in silicon oxide.

A new type of memristor inspired by bio-membranes is presented, based on the proton movement resulting from proton-coupled electron transfer (PCET) processes in dinuclear Ru complexes, whereby a two-terminal device based on said Ru complexes and a proton-conducting polymer was constructed as a proof-of-concept.

This study is focused on Conductive Bridging Random Access Memory (CBRAM) devices based on chalcogenide electrolyte and Cu-supply materials, and aims at identifying the key material parameters controlling memory properties.

In this paper, we want to review the correlation between filamentary (width) switching and the (SET) I–V characteristics by discussing the existing models.

Electrochemically grown anodic oxides of different compositions and properties were tested as solid electrolytes for resistive switching memories.

Here, we propose a technique, based on the electrochemical potential of dopant atoms in a material, that enables the dynamic control of the number of dopant atoms through the application of bias to the material.