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Area of Science:

  • Condensed Matter Physics
  • Quantum Field Theory
  • Nanotechnology

Background:

  • Fermionic systems exhibit quantum vacuum energy, influencing physical phenomena.
  • Boundary conditions significantly alter quantum effects in confined systems.
  • Condensation processes can modify vacuum energy contributions.

Purpose of the Study:

  • Investigate the impact of boundary conditions on quantum vacuum energy in finite fermionic chains.
  • Analyze the resulting Casimir force behavior under these conditions.
  • Understand the interplay between fermionic interactions, condensation, and vacuum energy.

Main Methods:

  • Utilized a self-consistent method for theoretical analysis.
  • Modeled a finite-length fermionic chain with interacting fermions.
  • Applied specific boundary conditions to the fermionic system.

Main Results:

  • Observed nontrivial behavior in the quantum vacuum energy.
  • The Casimir force exhibited a switch from an attractive to a repulsive regime.
  • Identified competition between attractive fermionic Casimir effect and repulsive condensate contribution.

Conclusions:

  • Boundary conditions in finite fermionic chains lead to significant alterations in quantum vacuum energy.
  • The Casimir force can transition from attractive to repulsive, driven by condensate effects.
  • This finding has implications for understanding Casimir forces in nanoscopic systems.