Inhomogeneous melting in anisotropically confined two-dimensional clusters

Area of Science:

• Condensed Matter Physics
• Computational Physics
• Statistical Mechanics

Background:

• Melting phenomena in confined systems are crucial for understanding material properties.
• Anisotropic potentials introduce complexities not seen in isotropic systems.
• Previous studies often focused on isotropic confinement or bulk materials.

Purpose of the Study:

• To investigate the melting process of 2D charged particle clusters in anisotropic potentials.
• To determine how confinement eccentricity influences melting patterns and temperatures.
• To characterize a novel melting behavior termed 'internal intershell melting'.

Main Methods:

• Molecular dynamic simulations were employed to model the system.
• Classical charged particles were confined in an anisotropic parabolic potential.
• Repulsive interparticle potentials (logarithmic and screened Coulomb) were used.
• Lindemann's criterion was applied to determine melting temperatures.

Main Results:

• Confinement potential eccentricity significantly alters cluster melting patterns.
• Three distinct melting regimes were identified as eccentricity increased.
• Internal intershell melting was observed, where central particles melt before peripheral ones.
• Melting temperatures varied with confinement parameters and interparticle interaction range.

Conclusions:

• Anisotropic confinement drives unique melting behaviors like internal intershell melting.
• The range of interparticle interactions affects the conditions under which internal intershell melting occurs.
• This study provides insights into phase transitions in geometrically constrained systems.