Nano‐Raman Spectroscopy of Tellurium Nanowires

ABSTRACT Tellurium‐based nanowires are interesting structures for applications in low‐dimensional electronics. This work investigates the vibrational dynamics of trigonal tellurium (t‐Te) nanowires through tip‐enhanced Raman spectroscopy (TERS), achieving spatial resolution in the 50‐nm range. The analysis revealed a dependence of the Raman active phonon mode frequency on nanowire diameter. Besides the observation of different frequencies for isolated nanowires with different diameters, we also observed changes of the mode frequency along the axis of a single nanowire that are consistent with diameter changes measured by in situ atomic force microscopy (AFM). Furthermore, we demonstrate that the mode frequency also changes along a single nanowire species due to local strain likely induced by the presence of amorphous material deposited on top. Our work thus provides detailed insights into the nanoscale vibrational and structural properties of t‐Te nanowires, highlighting the capabilities of TERS to study of Raman shifts along single nanowires.