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DOE OSTI · 1961801

Surface-sensitive photon avalanche behavior revealed by single-avalanching-nanoparticle imaging

Kwock, Kevin W. C.·Lee, Changhwan·Teitelboim, Ayelet·Liu, Yawei·Yao, Kaiyuan·Alam, Sardar B.·Cohen, Bruce E.·Chan, Emory M.·Schuck, P. James
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Abstract

Avalanching nanoparticles (ANPs) are a new class of lanthanide-based upconverting material demonstrating steep optical nonlinearities with the potential to advance applications ranging from subwavelength bioimaging to neuromorphic computing, nanothermometry, and pressure transduction. Here, we use single-nanocrystal imaging to uncover design-dependent heterogeneity in ANP threshold intensity (I th ). Quantitative comparisons between distributions of I th and ANP shell properties reveal correlations between mean I th values, histogram widths, and nanocrystal shell thickness. Evaluating avalanching behaviors using an established model of shell-dependent surface energy transfer shows that variations in shell thickness-and the resultant energy transfer through the shell to the surface and environment-are likely the primary contributor to ANP-to-ANP I th heterogeneity. Further, nanocrystals with an ~6 nm average shell thickness show I th heterogeneity beyond the extent expected from statistical measurements of shell size and variability using transmission electron microscopy (TEM). Here these results provide a principal guide for the design and application of ANPs to environmental sensing.

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37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRYenergy transfernanoparticlesphysical and chemical propertiesthicknesstransmission electron microscopy

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Kwock, Kevin W. C., Lee, Changhwan, Teitelboim, Ayelet, Liu, Yawei, Yao, Kaiyuan, Alam, Sardar B., Cohen, Bruce E., Chan, Emory M., Schuck, P. James. 2021-10-27. Surface-sensitive photon avalanche behavior revealed by single-avalanching-nanoparticle imaging. https://doi.org/10.1021/acs.jpcc.1c07721

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