Raman spectroscopy of monolayer to bulk PtSe2 exfoliated crystals

Raman spectroscopy is widely used to assess the quality of 2D materials thin films. This report focuses on PtSe2 , a noble transition metal dichalcogenide which has the remarkable property to transit from a semi-conductor to a semi-metal with increasing layer number. While polycrystalline PtSe2 can be grown with various crystalline qualities, getting insight into the monocrystalline intrinsic properties remains challenging. We report on the study of exfoliated 1–10 layers PtSe2 by Raman spectroscopy, featuring record linewidth. The clear Raman signatures allow layer-thickness identification and provides a reference metrics to assess crystal quality of grown films.