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Coherent quantum transport features in carbon superlattice structures.
R McIntosh1, S J Henley2, S R P Silva2
1Nano-scale Transport Physics Laboratory, School of Physics, and Centre of Excellence in Strong Materials, University of the Witwatersrand, Private Bag 3, WITS 2050, Johannesburg, South Africa.
Scientific Reports
|October 21, 2016
Summary
Researchers explored resonant transmission in disordered diamond-like carbon superlattices. They demonstrated coherent quantum transport and negative differential resistance, paving the way for high-frequency carbon electronics.
Area of Science:
- Materials Science
- Condensed Matter Physics
- Nanotechnology
Background:
- Resonant transmission is well-understood in crystalline superlattices but not in disordered ones.
- Disordered diamond-like carbon (DLC) superlattices present challenges for conventional models due to structural disorder.
- Tuning resonant transmission in these disordered systems requires new approaches.
Purpose of the Study:
- To investigate resonant transmission in disordered DLC superlattices.
- To develop a theoretical model that accounts for structural disorder.
- To demonstrate coherent quantum transport effects in these novel structures.
Main Methods:
- Fabrication of DLC superlattices with varying sp³ hybridization.
- Experimental measurement of current-voltage (I-V) characteristics.
- Theoretical modeling using tight-binding calculations with simulated bond-length disorder.
Main Results:
- Demonstration of coherent quantum transport effects in disordered DLC superlattices.
- Observation of distinct current modulation and negative differential resistance (NDR).
- Model calculations successfully complemented experimental data, explaining transport phenomena.
Conclusions:
- Near-field structural order in DLC superlattices aids in confining quantized states, despite structural disorder.
- The developed model provides a guide for engineering future devices.
- This work offers significant potential for developing high-frequency, large-area carbon electronics.
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