First-order depinning transition of a driven interface in disordered media

Area of Science:

• Physics
• Materials Science
• Complex Systems

Background:

• Disordered media present complex phenomena in physical systems.
• Pinning-depinning (PD) transitions are crucial for understanding interface dynamics in such media.
• Characterizing the nature (continuous vs. first-order) of PD transitions is essential for predicting material behavior.

Purpose of the Study:

• To introduce a novel, simple growth model that exhibits a first-order pinning-depinning (PD) transition.
• To investigate the mechanism driving the first-order PD transition, specifically the role of local inertia.
• To explore the phase transitions and critical exponents associated with the model's dynamical behavior.

Main Methods:

• Development of a simple growth model incorporating local inertia forces.
• Analysis of the model's behavior under varying parameters to identify transition points.
• Measurement of critical exponents to characterize the dynamical properties of the transitions.

Main Results:

• The model demonstrates a tunable PD transition, switching between continuous and first-order based on a parameter 'p'.
• A first-order PD transition is triggered when the local inertia force exceeds a critical threshold (p > p(c)).
• The model also exhibits a distinct phase transition from a fluctuating to a non-fluctuating interface with constant velocity.

Conclusions:

• The introduced growth model provides a simplified framework for studying first-order PD transitions in disordered systems.
• Local inertia is identified as a key factor capable of inducing first-order PD transitions.
• The model's dual transition behavior offers insights into the complex dynamics of interfaces in disordered media.