Scanning transmission electron microscopy (STEM) thermometry techniques offer the potential for mapping temperature (T) with high spatial resolution. Existing STEM thermometry methods based on thermally induced strains must contend with small thermal expansion coefficients [<10 parts per million (ppm)/K] for some materials of interest, as well as non-local relationships between strain and temperature. In contrast, the well-known mechanism of thermal diffuse scattering (TDS) offers promise for inherently local T measurements with larger temperature coefficients (>1000 ppm/K) for almost all materials at room temperature. This T-dependent TDS has not been leveraged for STEM thermometry, however, due to experimental difficulties in quantifying the relatively small thermal signals. Here, we demonstrate quantitative TDS measurements using STEM by measuring diffuse scattering in energy-filtered scanning electron nanodiffraction patterns. Applying virtual apertures to these diffraction patterns during post-processing allows us to quantify the T-dependent TDS between the Bragg spots. We measure a position-averaged temperature coefficient of 2400±400 ppm/K for a single-crystal gold film averaged between T=100 K and T=300 K and compare this result with the predictions of Debye-Waller theory. This TDS-based STEM thermometry technique demonstration provides a step towards the goal of non-contact nanoscale temperature mapping of thin nanostructures.
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