An atomic Boltzmann machine capable of self-adaption

Autor: Hilbert J. Kappen, Elze J. Knol, Werner M. J. van Weerdenburg, Brian Kiraly, Alexander A. Khajetoorians
Rok vydání: 2021
Předmět:
Zdroj: Nature Nanotechnology, 16, 414-420
Nature Nanotechnology
Nature Nanotechnology, 16, pp. 414-420
ISSN: 1748-3387
Popis: The quest to implement machine learning algorithms in hardware has focused on combining various materials, each mimicking a computational primitive, to create device functionality. Ultimately, these piecewise approaches limit functionality and efficiency, while complicating scaling and on-chip learning, necessitating new approaches linking physical phenomena to machine learning models. Here, we create an atomic spin system that emulates a Boltzmann machine directly in the orbital dynamics of one well-defined material system. Utilizing the concept of orbital memory based on individual cobalt atoms on black phosphorus, we fabricate the prerequisite tuneable multi-well energy landscape by gating patterned atomic ensembles using scanning tunnelling microscopy. Exploiting the anisotropic behaviour of black phosphorus, we realize plasticity with multi-valued and interlinking synapses that lead to tuneable probability distributions. Furthermore, we observe an autonomous reorganization of the synaptic weights in response to external electrical stimuli, which evolves at a different time scale compared to neural dynamics. This self-adaptive architecture paves the way for autonomous learning directly in atomic-scale machine learning hardware. Stochastic orbital dynamics of individually coupled Co atoms on black phosphorus enables the realization of a Boltzmann machine capable of self-adaption.
Databáze: OpenAIRE