TITLE:
Localization of Charge Carriers in Monolayer Graphene Gradually Disordered by Ion Irradiation
AUTHORS:
Erez Zion, Avner Haran, Alexander Butenko, Leonid Wolfson, Yuri Kaganovskii, Tal Havdala, Amos Sharoni, Doron Naveh, Vladmir Richter, Moshe Kaveh, Eugene Kogan, Issai Shlimak
KEYWORDS:
Graphene, Localization, Hopping Conductivity, Ion Irradiation
JOURNAL NAME:
Graphene,
Vol.4 No.3,
July
28,
2015
ABSTRACT: Gradual localization of charge carriers is studied in a series of microsize samples of monolayer graphene fabricated on the common large scale film and irradiated by different doses of C+ ions with energy 35 keV. Measurements of the temperature dependence of conductivity and magneto-resistance in fields up to 4 T show that at low disorder, the samples are in the regime of weak localization and antilocalization. Further increase of disorder leads to strong localization regime, when conductivity is described by the variable-range-hopping (VRH) mechanism. A crossover from the Mott regime to the Efros-Shklovskii regime of VRH is observed with decreasing temperature. Theoretical analysis of conductivity in both regimes shows a remarkably good agreement with experimental data.