Critical wetting transitions in two-dimensional systems subject to long-ranged boundary fields

Area of Science:

• Statistical Mechanics
• Condensed Matter Physics
• Surface Science

Background:

• Interface delocalization transitions are crucial in understanding phase behavior.
• Long-ranged boundary fields in two-dimensional (2D) systems present unique theoretical challenges.
• Previous effective interface models suggested limitations for critical wetting transitions under specific field conditions.

Purpose of the Study:

• To investigate interface delocalization transitions in wide 2D Ising strips.
• To determine the existence and conditions for critical wetting transitions under long-ranged boundary fields.
• To reassess the validity of effective interface models in such systems.

Main Methods:

• Utilizing the quasiexact density-matrix renormalization-group method.
• Performing ground-state analysis of the 2D Ising model.
• Analyzing interface potentials decaying as l(-delta) for large distances l.

Main Results:

• Explicit calculations confirm the existence of critical wetting transitions.
• These transitions occur even when effective interface potentials decay slowly (delta<2).
• The study determines the wetting phase diagram for various delta values, including delta=2 and delta=4.9.

Conclusions:

• Critical wetting transitions are demonstrated to exist in semi-infinite 2D systems under specific long-ranged boundary fields.
• The findings supersede previous claims that limited the occurrence of such transitions.
• The reliability limits of effective interface models are highlighted, emphasizing the need for more robust theoretical approaches.