Improved method for determining crystallographic orientation of strained graphene by Raman spectroscopy

Abstract

Strain-induced phenomena in graphene strongly depend on the strain direction with respect to the crystallographic orientation of graphene. The conventional method for determining the strain direction in graphene uses the polarized Raman spectroscopy of the G band and needs accurate alignment of the polarizer angle, which is not easy in a conventional Raman microscope equipped with a simple sample stage, and leads to an error in the strain direction. Here we develop a method of obtaining both the strain direction and the polarizer angle simultaneously from the polarized Raman spectroscopy of the G and 2D bands.