NANOscientific

Search
검색하기
overview
registration
speakers
program
Back to List

Host & Keynote Speaker

Dr. Martin Rejhon

Faculty of Mathematics and Physics, Charles University, Czech Republic

Electrical AFM modes for investigating ABC-stacked graphene domains in epitaxial graphene

 

 

In graphene, emergent properties ranging from superconductivity to ferroelectricity have been observed in ABC-stacked domains. These domains are typically obtained through exfoliation followed by expert mechanical twisting and alignment to the desired orientation, a process that is highly challenging and not scalable.

 

Here, we demonstrate that ABC-stacked graphene domains can be obtained using a scalable growth technique, namely the thermal decomposition of silicon carbide. Using conductive atomic force microscopy (c-AFM), we identified distinct conductivity patterns in untwisted trilayer epitaxial graphene grown on silicon carbide. These patterns revealed the presence of both ABA and ABC domains (Fig. 1a), consistent with the conductivity differences observed in twisted exfoliated graphene and predicted by density functional theory. Similar patterns were also observed using scanning microwave impedance microscopy (sMIM), which revealed distinct resistance (Fig. 1b) and capacitance (Fig. 1c) signatures for ABA and ABC stackings (Fig. 1b) arising from their different electronic band structures.
 

We further demonstrate that these moiré patterns are driven by strain present in the graphene system, allowing us to control the domain size by tuning the strain (Fig. 1a). This finding opens the way for future electronic and optoelectronic applications requiring large-area ABC-stacked graphene domains.

 

Figure 1 a)c-AFM image of an epitaxial graphene film with visible stripes in conductivity on a three layeref epitaxial graphene and change in Moire pattern after strain engineering. b) Resistance and c) capacitance signal from sMIM measurement.

We use cookies or similar technologies as specified in our privacy policy to enhance your experience.

If you would like to learn more about how we use cookies, click "Cookie Policy".