Quantum Gas-Enabled Direct Mapping of Active Current Density in Percolating Networks of Nanowires

Nano Lett. 2024 Jan 31;24(4):1309-1315. doi: 10.1021/acs.nanolett.3c04190. Epub 2024 Jan 23.

Abstract

Electrically percolating nanowire networks are among 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 rerouting 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 materials. We introduce Bose-Einstein condensate microscopy to address the longstanding problem of imaging active current flow in 2D materials. We report on performance improvement 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 modeling individual junction behavior and hot-spot formation. Investigating both reversible and irreversible mechanisms will contribute to improved performance and reliability of devices.

Keywords: active current density imaging; percolation networks; quantum technology; silver nanowires; transparent conductive materials; ultrasensitive magnetometry.