The vibrational spectra of CdSe/CdS superlattices (SLs) with different layer thicknesses are calculated from first principles within the density functional theory. It is shown that, along folded acoustic and confined optical modes, a number modes appear in SLs. In structures minimum thickness one layers, microscopic interface similar to local gap crystals appear. An analysis projections eigenve...

Phonon transport across a vacuum gap separating intrinsic silicon crystals is predicted via the atomistic Green's function method combined with first-principles calculations of all interatomic force constants. The overlap electron wave functions in generates weak covalent interaction between surfaces, thus creating pathway for phonons. transport, dominated by acoustic modes, exceeds near-field ...