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Secondary Electron Interference from Trigonal Warping in Clean Carbon Nanotubes.
A Dirnaichner1,2, M Del Valle2, K J G Götz1
1Institute for Experimental and Applied Physics, University of Regensburg, 93040 Regensburg, Germany.
Physical Review Letters
|October 30, 2016
Summary
We observed secondary interference in carbon nanotube resonators, revealing insights into electron scattering. This allows for estimating the nanotube's chiral angle, crucial for understanding electronic properties.
Area of Science:
- Condensed Matter Physics
- Materials Science
- Nanotechnology
Background:
- Fabry-Perot interference is a key phenomenon in understanding electron transport in nanostructures.
- Carbon nanotubes exhibit unique electronic properties due to their one-dimensional structure and Dirac cone band structure.
- Investigating interference patterns can reveal details about scattering mechanisms and material properties.
Purpose of the Study:
- To investigate secondary interference patterns in an ultraclean carbon nanotube resonator.
- To identify the origin of the observed conductance modulation.
- To utilize the secondary interference for estimating the chiral angle of the carbon nanotube.
Main Methods:
- Fabrication and characterization of an ultraclean carbon nanotube resonator.
- Measurement of electrical conductance as a function of gate voltage.
- Analysis of fast and slow oscillations in the conductance data, including sliding average techniques.
Main Results:
- Observed a clear superstructure superimposed on conventional Fabry-Perot oscillations in the conductance.
- Identified a characteristic slow modulation of conductance related to trigonal warping of Dirac cones.
- Attributed the secondary interference to intervalley and intravalley backscattering processes.
Conclusions:
- The secondary interference pattern provides a novel method for probing electron scattering in carbon nanotubes.
- The analysis of this pattern allows for the estimation of the carbon nanotube's chiral angle.
- This work offers a new approach to characterize the electronic properties of carbon nanotubes.
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