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Negative differential resistance effect in planar graphene nanoribbon break junctions
Phuong Duc Nguyen1, Thanh Cong Nguyen, Faruque M Hossain
1Centre for Neural Engineering, Bld 261, 203 Bouverie St and The University of Melbourne, Parkville, VIC 3010, Australia.
Nanoscale
|November 20, 2014
Summary
Researchers developed a novel graphene nanoribbon device exhibiting negative differential resistance (NDR). This breakthrough, achieved by creating a nanogap, paves the way for advanced electronic circuit components.
Area of Science:
- Materials Science
- Condensed Matter Physics
- Nanotechnology
Background:
- Graphene possesses unique electrical properties, making it a promising material for electronic devices.
- Negative differential resistance (NDR) devices are crucial for implementing various electronic circuit elements.
- Existing fabrication methods for graphene-based NDR devices can be complex.
Purpose of the Study:
- To propose and demonstrate a novel single-layer graphene device exhibiting NDR.
- To utilize standard lithography techniques for fabricating the proposed device structure.
- To investigate the NDR phenomenon in graphene nanoribbon (GNR) junctions with a nanogap.
Main Methods:
- Theoretical simulations were performed on graphene nanoribbon junctions with engineered gaps.
- Graphene nanoribbon devices were fabricated using standard lithography.
- Electro-migration was employed to create a nanogap within the GNR, confirmed by scanning electron microscopy.
Main Results:
- Simulations predicted NDR in GNR junctions with a transport-direction gap.
- Experimental verification confirmed the NDR phenomenon in the fabricated GNR device with a tunnel gap.
- Current-voltage (I-V) characteristics before and after breakdown demonstrated the NDR effect originating from the nanogap.
Conclusions:
- A novel, lithographically fabricated single-layer graphene device exhibiting NDR has been successfully demonstrated.
- The introduction of a nanogap in a GNR is a viable method for achieving NDR.
- This research validates the potential of graphene nanoribbons with engineered gaps for future electronic applications.
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