Related papers: Acoustic phonons and strain in core/shell nanowire…
We formulate and study the effective low-energy quantum theory of interacting long-wavelength acoustic phonons in carbon nanotubes within the framework of continuum elasticity theory. A general and analytical derivation of all three- and…
One way to reduce the lattice thermal conductivity of solids is to induce additional phonon surface scattering through nanostructures. However, how phonons interact with boundaries, especially at the atomic level, is not well understood. In…
We report results of inelastic neutron scattering measurements of phonon dispersions in optimally doped YBa2Cu3O6.95 and compare them with model calculations. The focus is on the in-plane oxygen bond-stretching phonon branches. The study of…
The dynamics of the one-dimensional array of the single-walled carbon nanotubes, which interact by van der Waals forces, is considered. The molecular dynamics simulation shows that both the mutual displacements of the nanotubes and the…
The great possibilities for strain engineering in core/shell nanowires have been explored as an alternative route to tailor the properties of binary III-V semiconductors without changing their chemical composition. In particular, we…
Dynamics of dissipation of a local phonon distribution to the substrate is a key issue in friction between sliding surfaces as well as in boundary lubrication. We consider a model system consisting of an excited nano-particle which is…
Band structures encode electronic, optical, and acoustic properties of matter and can serve as an essential tool in material discovery and design. Dispersion anomalies -- sharp, non-standard features in the frequency-wavenumber relation --…
We report results of inelastic neutron scattering measurements of phonon dispersions on a detwinned sample of YBaCu3O7 and compare them with model calculations. Plane oxygen bond stretching phonon branches disperse steeply downwards from…
This paper is concerned with an asymptotic analysis of the dispersion relation for wave propagation in an elastic layer of uniform thickness. The layer is subject to an underlying simple shear deformation accompanied by an arbitrary uniform…
Direct measurement of local phonon dispersion in individual nanostructures can greatly advance our understanding of their electrical, thermal, and mechanical properties. However, such experimental measurements require extremely high…
The new regime of low-temperature heat transfer in suspended nanowires is predicted. It takes place when (i) only ``acoustic'' phonon modes of the wire are thermally populated and (ii) phonons are subject to the effective elastic…
We study heat current autocorrelation function and thermal conductivity in core-shell nanowires by using molecular dynamics simulations. Interestingly, a remarkable oscillation effect in heat current autocorrelation function is observed in…
We present a first-principles study on lattice vibrational modes of Si/Ge core-shell nanowires (NWs). In addition to quantum confinement, the internal strain induced by the lattice mismatch between core and shell contributes to significant…
The spontaneous bending of core-shell nanowires through asymmetric shell deposition has implications for sensors, enabling both parallel fabrication and creating advantageous out-of-plane nanowire sensor geometries. This study investigates…
Freestanding semiconductor nanowires have opened up new possibilities for semiconductor devices, enabling geometries, material combinations and strain states which were not previously possible. Along these lines, spontaneous bending in…
We obtain the the long-wavelength polar optical vibrational modes of semiconductor core-shell nanowires by means of a phenomenological continuum model. A basis for the space of solutions is derived, and by applying the appropriate boundary…
We investigate the effects of electron and acoustic-phonon confinement on the low-field electron mobility of thin square silicon nanowires (SiNWs) that are surrounded by SiO$_2$ and gated. We employ a self-consistent…
Strain engineering is critical to the performance enhancement of electronic and thermoelectric devices because of its influence on the material thermal conductivity. However, current experiments cannot probe the detailed physics of the…
The highly distinctive phonon self-energy dependences on the wave vector, calculated respectively for the static and dynamic stripe phase models of the underdoped cuprates are presented. The negative values of the real part of the on-stripe…
All solids, whether crystalline or disordered, support elastic wave propagation with a linear dispersion relation in the long-wavelength limit. These waves, corresponding to low-frequency phonons, feature a vibrational density of states…