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arXiv · 2303.12035

Quantum gas-enabled direct mapping of active current density in percolating networks of nanowires

Abstract

Electrically percolating nanowire networks are amongst the most promising candidates for next-generation transparent electrodes. Scientific interest in these materials stems from their intrinsic current distribution heterogeneity, leading to phenomena like percolating pathway re-routing and localized self-heating, which can cause irreversible damage. Without an experimental technique to resolve the current distribution, and an underpinning nonlinear percolation model, one relies on empirical rules and safety factors to engineer these materials. We introduce Bose-Einstein microscopy to address the long-standing problem of imaging active current flow in 2D materials. We report on improvement of the performance of this technique, whereby observation of dynamic redistribution of current pathways becomes feasible. We show how this, combined with existing thermal imaging methods, eliminates the need for assumptions between electrical and thermal properties. This will enable testing and modelling individual junction behaviour and hotspot formation. Investigating both reversible and irreversible mechanisms will contribute to the advancement of devices with improved performance and reliability.

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BibTeXRIS

J. Fekete, P. Joshi, T. J. Barrett, T. M. James, R. Shah, A. Gadge, S. Bhumbra, F. Oručević, P. Krüger. 2023-03-21. Quantum gas-enabled direct mapping of active current density in percolating networks of nanowires. https://doi.org/10.1021/acs.nanolett.3c04190

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