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DOE OSTI · 3380415

Quantum graph models for transport in filamentary switching

Silva, Alison A. [Universidade Estadual de Ponta Grossa (Brazil)] (ORCID:0000000335528780)·Andrade, Fabiano M. [Universidade Estadual de Ponta Grossa (Brazil)] (ORCID:0000000153836168)·Caravelli, Francesco [Los Alamos National Laboratory (LANL), Los Alamos, NM (United States)] (ORCID:0000000179643030)
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Abstract

The formation of metallic nanofilaments bridging two electrodes across an insulator is a mechanism for resistive switching. Examples of such phenomena include atomic synapses, which constitute a distinct class of memristive devices the behavior of which is closely tied to the properties of the filament. Until recently, experimental investigation of the low-temperature regime and quantum transport effects has been limited. However, with growing interest in understanding the true impacts of the filament on device conductance, comprehending quantum effects has become crucial for quantum neuromorphic hardware. Here, we discuss quantum transport resulting from filamentary switching in a narrow region where the continuous approximation of the contact is not valid, and only a few atoms are involved. In this scenario, the filament can be represented by a graph depicting the adjacency of atoms and the overlap between atomic orbitals. Using the theory of quantum graphs with locally diffusive node scattering, we calculate the scattering amplitude of charge carriers on this graph and explore the interplay between filamentary formation and quantum transport effects.

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71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICSconductancegraphsmemristorsnon-equilibrium

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Silva, Alison A. [Universidade Estadual de Ponta Grossa (Brazil)] (ORCID:0000000335528780), Andrade, Fabiano M. [Universidade Estadual de Ponta Grossa (Brazil)] (ORCID:0000000153836168), Caravelli, Francesco [Los Alamos National Laboratory (LANL), Los Alamos, NM (United States)] (ORCID:0000000179643030). 2025-01-22. Quantum graph models for transport in filamentary switching. https://doi.org/10.1103/physrevb.111.045145

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