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One-Dimensional Poole-Frenkel Conduction in the Single Defect Limit
Deng Pan1, Elliot J Fuller1, O Tolga Gül1
1Department of Physics and Astronomy, University of California at Irvine, Irvine, California 92697, United States.
Nano Letters
|July 21, 2015
Summary
Disorder in one-dimensional conductors was studied using semimetallic carbon nanotubes with single point defects. A modified Poole-Frenkel mechanism explains the observed high resistance and defect scattering in these systems.
Area of Science:
- Condensed matter physics
- Materials science
- Nanotechnology
Background:
- One-dimensional (1D) conductors are crucial for understanding quantum phenomena.
- Disorder significantly impacts electronic properties in 1D systems.
- Carbon nanotubes (CNTs) offer a near-ideal platform for studying 1D physics.
Purpose of the Study:
- To investigate the effects of single point defects on the electronic transport properties of semimetallic single-walled carbon nanotubes (SWNTs).
- To compare experimental findings with theoretical models of disorder in 1D conductors.
Main Methods:
- Fabrication and characterization of individual SWNTs before and after introducing single point defects.
- Transport measurements to analyze electrical conductance.
- Local Kelvin Probe force microscopy (LKPFM) to probe local electronic potential.
Main Results:
- Single point defects create wide (over 1.0 μm) high-resistance depletion regions in semimetallic SWNTs.
- Conductance through these depletion regions is governed by a modified, 1D Poole-Frenkel field-assisted emission mechanism.
- This mechanism effectively describes defect scattering and resistance in the semimetallic SWNT system.
Conclusions:
- The Poole-Frenkel mechanism provides a viable model for understanding defect-induced resistance in 1D semimetallic systems.
- This research bridges a gap between theoretical predictions and experimental observations of disorder in 1D conductors.
- The findings contribute to the fundamental understanding of electron transport in nanostructured materials.
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