Skip to main content

Thank you for visiting nature.com. You are using a browser version with limited support for CSS. To obtain the best experience, we recommend you use a more up to date browser (or turn off compatibility mode in Internet Explorer). In the meantime, to ensure continued support, we are displaying the site without styles and JavaScript.

2D MATERIALS

Edge state mitigation

Nat. Commun. 10, 230 (2019)

Graphene quantum dots (GQDs), a relatively new addition to the nanocarbon materials family, have a number of advantageous tunable opto-electronic properties. However, the presence of localized edge states in GQDs, which inevitably occur during their formation, adversely affects the charge transport. Moreover, the fabrication of tunnelling contacts to GQDs with reproducible contact resistances has proved challenging. Now, G. Kim and colleagues have shown how to circumvent these issues by using a combination of in-plane and vertical heterostructures to build vertical single-electron tunnelling transistors.

The researchers synthesize the GQDs on top of an array of platinum nanoparticles embedded inside a hexagonal boron nitride (hBN) matrix through catalytic substitution of boron and nitrogen atoms by carbon. The GQD/hBN layer is sandwiched between two thin hBN layers to isolate the quantum dots from the contacts: this ensures a long lifetime of electrons and reduces the number of localized states. Next, multichannel single-electron tunnelling transistors are prepared by capping the GQD/hBN structure with graphene electrodes. Differential conductance measurements performed using tunnelling spectroscopy reveal the observation of multiple Coulomb diamonds originating from a Coulomb blockade regime in one particular GQD.

Author information

Authors and Affiliations

Authors

Corresponding author

Correspondence to Kanudha Sharda.

Rights and permissions

Reprints and Permissions

About this article

Verify currency and authenticity via CrossMark

Cite this article

Sharda, K. Edge state mitigation. Nature Nanotech 14, 100 (2019). https://doi.org/10.1038/s41565-019-0388-z

Download citation

  • Published:

  • Issue Date:

  • DOI: https://doi.org/10.1038/s41565-019-0388-z

Search

Quick links

Find nanotechnology articles, nanomaterial data and patents all in one place. Visit Nano by Nature Research