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Title: Impact of nuclear vibrations on van der Waals and Casimir interactions at zero and finite temperature
Recent advances in measuring van der Waals (vdW) interactions have probed forces on molecules at nanometric separations from metal surfaces and demonstrated the importance of infrared nonlocal polarization response and temperature effects, yet predictive theories for these systems remain lacking. We present a theoretical framework for computing vdW interactions among molecular structures, accounting for geometry, short-range electronic delocalization, dissipation, and collective nuclear vibrations (phonons) at atomic scales, along with long-range electromagnetic interactions in arbitrary macroscopic environments. We primarily consider experimentally relevant low-dimensional carbon allotropes, including fullerenes, carbyne, and graphene, and find that phonons couple strongly with long-range electromagnetic fields depending on molecular dimensionality and dissipation, especially at nanometric scales, creating delocalized phonon polaritons that substantially modify infrared molecular response. These polaritons, in turn, alter vdW interaction energies between molecular and macroscopic structures, producing nonmonotonic power laws and nontrivial temperature variations at nanometric separations feasible in current experiments.  more » « less
Award ID(s):
1719875
PAR ID:
10146331
Author(s) / Creator(s):
; ; ; ;
Date Published:
Journal Name:
Science Advances
Volume:
5
Issue:
11
ISSN:
2375-2548
Page Range / eLocation ID:
eaaw0456
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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