Statistics of Critical Avalanches in Vertical Nanopillar Arrays

Nanopillar arrays are encountered in numerous areas of nanotechnology such as bio-medical and chemical sensing, nanoscale electronics, photovoltaics or thermoelectrics. Especially arrays of nanopillars subjected to uniaxial microcompression reveal the potential applicability of nanopillars as components for the fabrication of electro-mechanical sense devices. Thus, it is worth to analyze the failure progress in such systems of pillars. Under the growing load pillars destruction forms an avalanche and when the load exceeds a certain critical value the avalanche becomes self-sustained until the system is completely destroyed. In this work we have explored the distributions of such catastrophic avalanches appearing in overloaded systems. Specifically, we analyze the relations between the size of an avalanche being the numbers of instantaneously crushed pillars and the size of the corresponding array of nanopillars using different load transfer protocols.