Carrier dynamics in ordered-disorder 2D Materials

We report on the fabrication and characterization of ordered disorder single-layer (OD-SL) graphene, a structure that contains defects with their own periodicity, distinct from the underlying lattice, resembling a superlattice. It has been theoretically proposed that graphene with periodic pores or vacancies can exhibit flat bands due to a high degree of Anderson-like localized states. Various methods, including atomic force microscopy and photolithography, have been suggested to realize OD-SL. In this work, we present our results on the fabrication of single and multilayer graphene with periodic defects using Ar+ ion bombardment, characterized through micro-Raman spectroscopy and ultrafast photoconductance measurements across different temperatures. We will also present and analyze the variation in transient photoconductivity of OD-SL for different laser excitation wavelengths (800-1100 nm) using an ultrafast laser with 130-fs pulses. The analysis will be based on wavefunction localization in OD- SL, modeled using the Kwant and Tkwant packages.