Abstract

The phonon thermal conductance of sub-nanometric vacuum gaps between two in-plane nanoribbons of two-dimensional materials (graphene and silicene) is analyzed using the atomistic Green’s function method and by employing the Tersoff and Lennard-Jones potentials for describing the interatomic interactions. It is found that the phonon conductance decays exponentially with the size of the gap, with distinct exponential regimes depending on the balance of repulsive and attractive Lennard-Jones interactions. The contribution from optical phonons is non-negligible only for very small gaps in graphene, and the conductance varies only modestly with nanoribbon width.

Abstract

The phonon thermal conductance of sub-nanometric vacuum gaps between two in-plane nanoribbons of two-dimensional materials (graphene and silicene) is analyzed using the atomistic Green’s function method and by employing the Tersoff and Lennard-Jones potentials for describing the interatomic interactions. It is found that the phonon conductance decays exponentially with the size of the gap, with distinct exponential regimes depending on the balance of repulsive and attractive Lennard-Jones interactions. The contribution from optical phonons is non-negligible only for very small gaps in graphene, and the conductance varies only modestly with nanoribbon width.

Abstract

The phonon thermal conductance of sub-nanometric vacuum gaps between two in-plane nanoribbons of two-dimensional materials (graphene and silicene) is analyzed using the atomistic Green’s function method and by employing the Tersoff and Lennard-Jones potentials for describing the interatomic interactions. It is found that the phonon conductance decays exponentially with the size of the gap, with distinct exponential regimes depending on the balance of repulsive and attractive Lennard-Jones interactions. The contribution from optical phonons is non-negligible only for very small gaps in graphene, and the conductance varies only modestly with nanoribbon width.

Abstract

The phonon thermal conductance of sub-nanometric vacuum gaps between two in-plane nanoribbons of two-dimensional materials (graphene and silicene) is analyzed using the atomistic Green’s function method and by employing the Tersoff and Lennard-Jones potentials for describing the interatomic interactions. It is found that the phonon conductance decays exponentially with the size of the gap, with distinct exponential regimes depending on the balance of repulsive and attractive Lennard-Jones interactions. The contribution from optical phonons is non-negligible only for very small gaps in graphene, and the conductance varies only modestly with nanoribbon width.