Synergetic Study of Electrical Transport using Graphene and SrTiO3

Tuesday, February 13, 2018 10:30 am - 10:30 am EST (GMT -05:00)

Jeongmin Park - Center for Integrated Nanostructure Physics (CINAP), Institute for Basic Science (IBS) Department of Energy Science, Sungkyunkwan University

The combination of two-dimensional (2D) materials and functional oxide has been attracted in electrical transport study. Many researchers expected synergetic performance from this interesting structure. And the field effect transistor (FET) scheme was widely used to study it. Here, we successfully demonstrated graphene FET device which is fabricated on top of SrTiO3 (STO).

First, we achieved low-voltage operating graphene FET using ultrahigh-k STO thin film as a gate dielectric. Moreover, the quantum Hall effect (QHE) was clearly observed in very small range of gate bias. In addition, the universality of QHE made it possible to deduce the dielectric properties of STO thin film. From these results, we concluded that our graphene-STO device could provide high performance with voltage scaling as designed. [1]

Second, using same device scheme, we studied oxygen vacancy (OV) dynamics in STO through conductance of graphene. The environmental sensitiveness of graphene enables to sense the generation/annihilation of OV simultaneously in non-destructive way.

In this study, the synergetic results through the combination of graphene and STO will be presented. Based on these results, we strongly suggest that this scheme is the worthwhile research having many opportunities for novel phenomena and physics. [2]

[1] J. Park, et al, Nano letters, 2016, 16.3: 1754-1759.
[2] K.T. Kang, et al, Advanced Materials, 2017, 29.18.