We report on our terahertz and optical study of monolayer graphene grown by chemical vapor deposition and processed by plasma oxidation. The plasma oxidation induces oxygen-related defects, and the resulting disorder increases the sheet resistance of graphene as measured via terahertz spectroscopy. The excitonic absorption peak weakens considerably and blue shifts upon plasma oxidation, resulting in higher transmittance in both the visible and ultraviolet regions. Our oxygen plasma-treated graphene also exhibits a free-carrier doping effect as confirmed by the blue shift of the Raman G band.
Bibliographical noteFunding Information:
This work was partially supported by the Quantum Metamaterial Research Center Program (Contract No. 2012-0000546), the Pioneer Research Center Program (2010-0019313), and the Priority Research Centers Program (2009-0093823) through the National Research Foundation (NRF) funded by the Ministry of Education, Science and Technology (MEST) of Korea.
All Science Journal Classification (ASJC) codes
- Physics and Astronomy (miscellaneous)