Indium Selenide (InSe) is a remarkable two-dimensional quantum material whose characteristic properties include a bandgap in the near infrared region that increases with fewer layers. InSe is known to crystallize in either the β-, γ- or the ε-phase. Of these three crystalline phases, only the β and γ exhibit a direct bandgap, which makes them suitable for optoelectronic applications. The β-phase is easily distinguished from the others by means of Transmission Electron Microscopy (TEM), whereas the γ- and ε-phases appear very similar. We determine the crystalline phase present in these InSe specimens by systematic investigation with High Resolution TEM. We further assess the local electronic properties using Electron Energy-Loss Spectroscopy (EELS) by mapping relevant features in the spectra. Finally, we deploy Machine Learning techniques for a model-independent subtraction of the Zero Loss Peak, making it possible to identify features in the ultra-low-loss region of the EELS spectra.
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