First-principles calculations of phonon transport across a vacuum gap
First-principles calculations of phonon transport across a vacuum gap
Phonon transport across a vacuum gap separating intrinsic silicon crystals is predicted via the three-dimensional atomistic Green's function method combined with first-principles calculations, based on the density functional theory, of all interatomic force constants. Phonon transport, dominated by acoustic modes, exceeds near-field radiation for vacuum gaps $d$ smaller than $\ensuremath{\sim}1$ …