Quantifying Temperature Susceptivity of Electron Scattering in Scanning Transmission Electron Microscopy

Phonons can influence the trajectory of incoming radiations and affect the outcome of any scattering experiment. Thus, proper quantification of the influence may provide the temperature of the material at the length scale equivalent to the size of the probe used in the scattering experiment. In this work, we report the sensitivity of electron scattering to sample temperature as a function of the scattering angle in scanning transmission electron microscopy (STEM). Unlike the scattering intensities at higher angle ranges that are known to be dominated by thermal diffuse scattering, the temperature sensitivity of the intensities at lower scattering angles has been less understood. We show that the scattering intensities at low-to-intermediate angles increase at higher temperatures, and the amplitude of the change is larger than that in the high angle range. This trend was observed in position averaged convergent beam electron diffraction as well as the atomic-scale images acquired from 4-dimensional STEM. Based on the finding, we quantified the trend as a function of both temperature and the scattering vector, which provides important guidance toward realizing the temperature measurement of materials with high-temperature precision and spatial resolution close to the atomic scale.