Origin of Current‐Controlled Negative Differential Resistance Modes and the Emergence of Composite Characteristics with High Complexity

Abstract

Current-controlled negative differential resistance has significant potential as a fundamental building block in brain-inspired neuromorphic computing. However, achieving desired negative differential resistance characteristics, which is crucial for practical implementation, remains challenging due to little consensus on the underlying mechanism and unclear design criteria. Here, we report a material-independent model of current-controlled negative differential resistance to explain a broad range of characteristics, including the origin of the discontinuous snap-back response observed in many transition metal oxides. This is achieved by explicitly accounting for a non-uniform current distribution in the oxide film and its impact on the effective circuit of the device, rather than a material-specific phase transition. The predictions of the model are then compared with experimental observations to show that the continuous S-type and discontinuous snap-back characteristics serve as fundamental building blocks for composite behaviour with higher complexity. Finally, we demonstrate the potential of our approach for predicting and engineering unconventional compound behaviour with novel functionality for emerging electronic and neuromorphic computing applications.

Negative Differential Resistance Characteristics in Forming‐Free NbOx with Crystalline NbO2 Phase

“…Various transition metal oxides such as TiO x , TaO x , VO x , and NbO x were reported to show NDR. [ 6–18 ] Among these oxides, NbO x films particularly exhibit two types of NDR characteristics, namely, S‐type [ 8–16 ] and snapback, [ 15–20 ] under current‐source measurement. Recent studies suggest that the continuous S‐type NDR in amorphous NbO x films is attributed to the temperature‐dependent Poole–Frenkel (P–F) model with local Joule heating.…”

“…[ 20 ] The S‐type NDR was explained using the P–F‐based conduction model, and the snapback NDR was attributed to MIT, which was evident from the abrupt reduction in the resistance at a high transition temperature of ≈1080 K. [ 21,22 ] Notably, it was reported that the irreversible crystallization of the NbO 2 phase occurred after the snapback NDR process. However, Li et al [ 15 ] recently proposed a material‐independent current redistribution model to explain the snapback NDR in non‐MIT materials. [ 8,23,24 ] In this study, the core–shell model [ 11 ] was applied, where a switching filament (i.e., core) with high conductivity was surrounded by a shell region with low conductivity.…”

A S-Type Bistable Locally-Active Memristor and Its Application in Oscillator Circuit

“…S-Type LAM is a nonlinear local active device, which is simpler in concept than the passive memristor with negative resistance, thus it can form an oscillation circuit without pure negative resistor. However, the S-Type LAMs are difficult to commercially access due to the technology and cost of manufacturing nano-scale electronic component [31]. Therefore, in order to enrich the theoretical knowledge of S-Type LAM and explore its practical application in various fields, it is necessary to further study the emulator and simulation model in the area of negative differential resistance (NDR).…”

Quantum transport in zigzag graphene nanoribbon decorated with a phenanthrene molecule

“…Many important breakthroughs have been achieved in molecular devices already [2][3][4][5][6][7][8]. By means of external electric field, deformations of the molecular and light incident, many intriguing properties have been acquired in the past years [9][10][11], such as negative differential resistance (NDR) [12][13][14][15][16][17][18][19][20][21], molecular rectification [1,[22][23][24][25], molecular switch [17,[26][27][28], and conductance enhancement [29][30]. Some related works [31][32][33][34], early reported, are of great value to promote the realization of quantum computer.…”