Irradiation-induced metal-insulator transition in monolayer graphene

Abstract

A brief review of experiments directed to study a gradual localization of charge carriers and metal-insulator transition in samples of disordered monolayer graphene is presented. Disorder was induced by irradiation with different doses of heavy and light ions. Degree of disorder was controlled by measurements of the Raman scattering spectra. The temperature dependences of conductivity and magnetoresistance (MR) showed that at low disorder, conductivity is governed by the weak localization and antilocalization regime. Further increase of disorder leads to strong localization of charge carriers, when the conductivity is described by the variable-range-hopping (VRH) mechanism. It was observed that MR in the VRH regime is negative in perpendicular fields and is positive in parallel magnetic fields which allowed to reveal different mechanisms of hopping MR. Theoretical analysis is in a good agreement with experimental data.

High-Performance InSe Photodetector Induced by Synergetic Surface Plasmon Resonance and Surface Engineering

“…Since the successful isolation of graphene by Geim and his colleagues in 2004, verifying the existence of naturally occurring two-dimensional (2D) crystals in nature, this layered 2D material has increasingly garnered widespread attention from researchers, sparking a new wave of material research. − However, the characteristic of graphene having a zero bandgap results in a low on/off ratio, high dark current, and poor optoelectronic performance in devices, significantly limiting its applications in the field of microelectronics . Layered 2D materials from the III-VI group, with their diverse bandgap structures, , unique optoelectronic properties, , and van der Waals surfaces without dangling bonds, greatly broaden the design dimensions for semiconductor electronic and optoelectronic devices.…”