Granular metals: From electronic correlations to strain-sensing applications

An analysis scheme is presented that allows for a quantitative description of the sensitivity of granular metal based strain sensors. The scheme draws on recent advances in the understanding of charge transport mechanisms in granular metals. How to deduct the relevant model parameters from temperature-dependent conductivity measurements is demonstrated by using recently published data for fcc-packed gold nanoparticle multilayers. Based on this model parameter set the intrinsic strain gauge factor is calculated as function of the intergrain coupling strength for different transport regimes. General trends for strain gauge factor optimization are identified. The absolute values for the calculated gauge factor are in good correspondence with typical values obtained for metal-containing diamondlike carbon thin film strain sensors. (C) 2010 American Institute of Physics. [doi: 10.1063/1.3443437]