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Updated: Jul 7, 2026
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Comprehensive Characterization of Extended Defects in Semiconductor Materials by a Scanning Electron Microscope
Published on: May 28, 2016
Inhomogeneous exclusion processes with extended objects: the effect of defect locations
J J Dong1, B Schmittmann, R K P Zia
1Center for Stochastic Processes in Science and Engineering, Department of Physics, Virginia Tech, Blacksburg, Virginia 24061-0435, USA. jjdong@vt.edu
Physical Review. E, Statistical, Nonlinear, and Soft Matter Physics
|February 1, 2008
Summary
Local defects in particle transport systems significantly alter flow. Simulations show particle size and defect location critically impact steady-state currents and density profiles.
Area of Science:
- Statistical Mechanics
- Condensed Matter Physics
- Biophysics
Background:
- The totally asymmetric simple exclusion process (TASEP) models particle transport on a line.
- Local inhomogeneities, such as slow sites, can disrupt uniform particle flow.
- Understanding these effects is crucial for modeling biological transport phenomena.
Purpose of the Study:
- To investigate the impact of local inhomogeneities (slow sites) on the TASEP.
- To compare the effects of these defects for particles of different sizes (l=1 vs. l>1).
- To analyze the influence of defect number and proximity on system dynamics.
Main Methods:
- Numerical simulations of the totally asymmetric simple exclusion process.
- Analysis of stationary current and density profiles.
- Examination of asymptotic behavior as hopping rate approaches zero (q-->0).
Main Results:
- Local defects qualitatively affect the steady state similarly for particles of size l=1 and l>1.
- A single slow site significantly influences the current based on its position.
- Two closely spaced slow sites can cause dramatic decreases in the stationary current.
- Asymptotic analysis (q-->0) reveals further details of defect-induced behavior.
Conclusions:
- Local inhomogeneities profoundly impact particle transport dynamics in TASEP.
- Particle size and defect arrangement are critical factors determining transport efficiency.
- Findings provide insights into biological transport mechanisms and potential bottlenecks.
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