Magnetocaloric Effect for a Q-Clock-Type System

Area of Science:

• Statistical physics
• Quantum mechanics
• Condensed matter physics

Background:

• The Q-state clock model describes systems with multi-state interactions, relevant to diverse fields.
• This model exhibits the Berezinskii-Kosterlitz-Thouless (BKT) phase for Q≥5, characterized by vortex states.

Purpose of the Study:

• To investigate the magnetocaloric effect (MCE) in the Q-state clock model.
• To determine the Q values that maximize MCE for different lattice sizes and magnetic field strengths.
• To analyze magnetic phase transitions associated with the MCE process.

Main Methods:

• Monte Carlo simulations were employed to calculate thermodynamic quantities.
• Simulations were performed for even Q values (2 to 8) on various lattice sizes (N=8x8 to 128x128).
• The magnetocaloric effect was quantified by analyzing entropy changes during isothermal magnetic field variations.

Main Results:

• The study identified specific Q values that lead to maximum MCE, dependent on lattice size.
• Magnetic phase transitions were observed and linked to the MCE process.
• The relationship between Q, lattice size, and MCE was elucidated.

Conclusions:

• The Q-state clock model provides a valuable framework for understanding MCE in multi-state systems.
• Findings offer insights into applied quantum mechanics and statistical physics.
• The research highlights the model's relevance in fields like percolation theory and neural networks.