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Nonlinear hopping transport in ring systems and open channels
Mario Einax1, Martin Körner, Philipp Maass
1Institut für Physik, Technische Universität Ilmenau, 98684 Ilmenau, Germany. mario.einax@tu-ilmenau.de
Physical Chemistry Chemical Physics : PCCP
|January 13, 2010
Summary
Anomalous large effective jump lengths in nonlinear hopping transport can occur in ordered systems. Rectification effects from disorder are significant in open channels but diminish in ring systems with size.
Area of Science:
- Condensed matter physics
- Nonlinear dynamics
- Statistical mechanics
Background:
- Nonlinear hopping transport is crucial for understanding charge carrier movement in various materials.
- Previous studies often focused on specific coupling mechanisms or simplified models.
Purpose of the Study:
- To investigate nonlinear hopping transport in 1D ring and open channel systems.
- To analytically derive current responses to constant bias and explore rectification effects.
- To compare the transport behavior of ring and open channel models under different conditions.
Main Methods:
- Analytical derivation of stationary current response to constant bias.
- Analysis of nonlinear and linear conductivity ratios.
- Numerical solutions for sinusoidal bias.
- Comparison of ring and open channel models.
Main Results:
- Anomalous large effective jump lengths observed in experiments can arise in ordered systems.
- Rectification effects due to site energy disorder become negligible in large ring systems.
- In open channels, disorder in jump barriers leads to persistent rectification effects.
- Ring models accurately describe open channel transport at intermediate/high frequencies.
Conclusions:
- Ordered systems can exhibit complex nonlinear transport phenomena.
- Disorder plays a critical role in rectification, with different behaviors in rings versus open channels.
- The choice of model (ring vs. open channel) is crucial for accurately capturing transport dynamics, especially at low frequencies.
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