Thermally induced correlation effects studied by Raman spectroscopy in PtSe2/Al2O3 systems†
Abstract
In this paper, we report the analysis of the Raman spectroscopy results of PtSe2 layers (ranging from 1 to 10 layers) deposited on an Al2O3 substrate, compared to those of the sub-micron thin flake and bulk PtSe2. The positions of typical PtSe2 Raman modes and the integral intensity ratios of the A1g and E1g bands are compared and discussed for all the systems considered in the temperature range from room temperature to 520 K. Moreover, the correlation plot of E1g and A1g is used to analyse the correlations of the dominant Raman modes in the PtSe2/Al2O3 systems, in which the frequency position (in-plane to out-of-plane) ratio exhibits a well-defined linear dependence on temperature.