Magneto-transport of graphene and quantum phase transitions in the quantum Hall regime

TL;DR

This paper investigates magneto-transport and quantum phase transitions in monolayer graphene under high magnetic fields, revealing disorder-dependent critical exponents crucial for graphene device engineering.

Contribution

It uncovers non-universal critical exponents in the quantum Hall regime of graphene, dependent on disorder type, advancing understanding of quantum phase transitions.

Findings

Critical exponents vary with disorder type

Disorder influences quantum Hall plateau-insulator transition

Results inform graphene nano-device design

Abstract

We studied the magneto-transport in SiO2 substrate-supported monolayer graphene and the quantum phase transitions that characterize the quantum Hall regime, using magnetic fields up to 28T and temperatures down to 4K. The analysis of the temperature dependence of the Hall and longitudinal resistivity reveals new non-universalities of the critical exponents of the plateau-insulator transition. These exponent depends on the type of disorder that governs the electrical transport, which knowledge is important for the design and fabrication of new graphene nano-devices.