Electrocaloric effect in cubic Hubbard nanoclusters.

Area of Science:

• Condensed Matter Physics
• Computational Materials Science
• Nanotechnology

Background:

• The electrocaloric effect (ECE) is a promising phenomenon for solid-state cooling technologies.
• Understanding ECE in nanoscopic systems is crucial for developing advanced materials.
• Strongly correlated systems offer unique pathways for manipulating ECE.

Purpose of the Study:

• To computationally investigate the electrocaloric effect in a cubic nanocluster.
• To analyze the influence of an external electric field on system thermodynamics.
• To explore the tunability and potential applications of ECE in nanoclusters.

Main Methods:

• Utilized an extended Hubbard model for an 8-site cubic nanocluster.
• Employed exact numerical diagonalization within the canonical ensemble formalism.
• Calculated entropy and specific heat as functions of temperature and electric field.

Main Results:

• Quantified the electrocaloric effect via isothermal entropy change.
• Predicted both direct and inverse electrocaloric effects based on model parameters.
• Demonstrated a quadratic dependence of entropy change on electric field variation.

Conclusions:

• The electrocaloric effect in nanoclusters is highly sensitive to Hubbard model parameters, allowing for tuning.
• ECE shows potential for applications in strongly correlated nanocluster systems.
• The study provides a foundation for designing materials with tailored electrocaloric responses.