IQSE AMO-CM LUNCH SEMINAR SERIES
"Tailoring the electronic properties of graphene by surface manipulation"
Drs. Sung Oh Woo1 and Winfried Teizer1,2
1Texas A&M University
2Tohoku University, Japan
The electronic properties of graphene are strongly dependent on the carrier density which can be affected locally by irradiation or surface adsorption. We will present recent work in several departmental research groups that utilize a range of techniques to achieve control of the carrier density locally [1-3]. We first show that the electronic properties of graphene change as a result of electron beam irradiation altering the local electron doping. As the irradiated graphene is then exposed to air, environmental molecules are adsorbed on graphene, and the electronic properties can be explained by charged impurity scattering. Similarly, we show that graphene is doped with electrons as a result of Li deposition on graphene at cryogenic temperatures. As temperature increases, the transport behavior of graphene changes, which we argue is primarily due to charged impurity scattering, originating from the reduction of the atomic Li adatoms on graphene.
 The effect of electron induced hydrogenation of graphene on its electrical transport properties. S. O. Woo and W. Teizer. Applied Physics Letters 103, 041603 (2013);  Electron beam induced molecular adsorption on graphene field effect transistors. S. O. Woo and W. Teizer. Carbon 93, 693 (2015);  Temperature dependent transport properties of graphene with Li adatoms. S. Woo, S. Hemmatiyan, T.D. Morrison, KDD Rathnayaka, I. F. Lyuksyutov, and D. G. Naugle, to be submitted.
Tuesday, April 4, 2017
IQSE seminar room (MPHY 578), 12:00 PM
Mitchell Physics Building
Institute for Quantum Science and Engineering
Texas A&M University
Lunch (sandwich) will to be served 15 minutes prior start time