Nonlinear effects in memristors with mobile vacancies

Area of Science:

• Condensed Matter Physics
• Materials Science
• Electrical Engineering

Background:

• Vacancy motion is fundamental to material properties.
• Local vacancy concentration is bounded, leading to nonlinear effects.
• Memristors exhibit resistance changes based on internal state.

Purpose of the Study:

• Investigate nonlinear effects in electric field-driven vacancy motion in memristors.
• Analyze the behavior of memristor resistance during state switching.
• Characterize the dependencies of switching and relaxation times on memristor dimensions.

Main Methods:

• Developed a simplified model for electric field-driven vacancy motion.
• Solved the nonlinear Burgers' equation with nonlinear boundary conditions exactly.
• Analyzed the resulting resistance dynamics and time dependencies.

Main Results:

• Observed non-monotonous resistance relaxation during switching between stable 'on' and 'off' states.
• Found distinct dependencies of switching time (under current) and relaxation time (without current) on memristor length.
• Identified nonlinear effects stemming from bounded vacancy concentrations.

Conclusions:

• The exact solution provides a benchmark for complex memristor simulations.
• Nonlinear dynamics significantly influence memristor switching behavior.
• Understanding these effects is crucial for memristor device design and optimization.