Phonon Casimir effect in polyatomic systems

The phonon Casimir effect describes the phonon-mediated interaction between defects in condensed-matter systems. Using path-integral formalism, we derive a general method for calculating Helmholtz free energy due to vibrational modes systems of arbitrary dimensionality and composition. Our results make it possible extract defect at any temperature various configurations. We demonstrate our approach action by performing numerical calculations mono- diatomic chains, as well molecule, zero finite temperatures validate using exact diagonalization.