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Driven flow with exclusion and spin-dependent transport in graphenelike structures
S L A de Queiroz1, R B Stinchcombe2
1Instituto de Física, Universidade Federal do Rio de Janeiro, Caixa Postal 68528, 21941-972 Rio de Janeiro, Rio de Janeiro, Brazil.
Physical Review. E
|May 17, 2017
Summary
We simplified spin-dependent electronic transport in honeycomb lattices using a nonequilibrium model. Double occupancy significantly impacts transport only under specific high injection and low ejection rates.
Area of Science:
- Condensed Matter Physics
- Mesoscopic Physics
- Quantum Transport
Background:
- Spin-dependent electronic transport is crucial for spintronics.
- Honeycomb lattices, like graphene, exhibit unique electronic properties.
- Spin-orbit interactions significantly influence electron behavior.
Purpose of the Study:
- To develop a simplified model for spin-dependent transport in honeycomb lattices.
- To investigate the role of Pauli exclusion and double occupancy in transport phenomena.
- To analyze the impact of particle injection and ejection rates on system dynamics.
Main Methods:
- Generalizations of the totally asymmetric simple exclusion process (TASEP).
- Mean-field theory for analytical insights.
- Numerical simulations for quantitative analysis.
Main Results:
- Model successfully describes currents, density profiles, and current polarization.
- Double occupancy effects are pronounced at high particle injection (α) and low ejection (β) rates.
- Quantitative impact of double occupancy is otherwise suppressed.
Conclusions:
- The simplified model provides a valuable framework for understanding complex transport phenomena.
- Findings suggest potential relevance for experiments on doped graphenelike materials.
- Control of injection/ejection rates can tune the influence of double occupancy.
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