Related papers: Thermally triggered phononic gaps in liquids at TH…
The understanding and modeling of the heat transport across nanometer and sub-nanometer gaps where the distinction between thermal radiation and conduction become blurred remains an open question. In this work, we present a…
We investigate the ultrafast dynamics of photo-induced non-thermal lattice disorder in a polycrystalline aluminium thin film to elucidate transient short- and long-range lattice distortions, their thermalization and electron-phonon coupling…
Classical thermal transport theories that preserve rotational symmetry, predict strong anharmonic scattering of out-of-plane lattice vibrational modes called flexural phonons in flat suspended graphene sheets. Such strong scattering…
Time-domain THz transmission experiment was performed on a $\rm SrBi_2Ta_2O_9$ film deposited on sapphire substrate. Temperatures between 300 and 923 K were investigated and complex permittivity spectra of the film were determined. The…
We study thermal transport through Pt nanowires that bridge planar contacts as a function of wire length and vibrational frequency of the contacts. When phonons in the contacts have lower average frequencies than those in the wires thermal…
We explore a novel coupling mechanism of electrons with the transverse optical (TO) phonon branch in a regime when the TO mode becomes highly anharmonic and drives the ferroelectric phase transition. We show that this anharmonicity, which…
Amorphous solids manifest puzzling effects of mysterious degrees of freedom that give rise to a heat capacity and phonon scattering in great excess over what would be expected for a solid that has a unique vibrational ground state. Of…
Phonons-quantized vibrational modes in crystalline structures-govern phenomena ranging from thermal and mechanical transport to quantum mechanics. In recent years, a new class of artificial materials called phononic crystals has emerged,…
The impact of lattice type, period, porosity and thickness of two-dimensional silicon phononic crystals on the reduction of thermal conductance by coherent modification of phonon dispersion is investigated using the theory of elasticity and…
We present an analysis of acoustic phonon propagation through long, free-standing, insulating wires with rough surfaces. Due to a crossover from ballistic propagation of the lowest-frequency phonon mode at $\omega <\omega _{1}=\pi c/W$ to a…
We suggest a new class of hyperbolic metamaterials for THz frequencies based on multilayer graphene structures. We calculate the dielectric permittivity tensor of the effective nonlocal medium with a periodic stack of graphene layers and…
Structured metamaterials are at the core of extensive research, promising for acoustic and thermal engineering. Nevertheless, the computational cost required for correctly simulating large systems imposes to use a continuous model to…
The propagation and the evolution of Alfvenic pulses in the solar coronal arcades is investigated by means of MHD numerical simulations. Significant transverse oscillations in coronal loops, triggered by nearby flare events, are often…
Static and dynamical properties of elastic phase transitions under the influence of short--range defects, which locally increase the transition temperature, are investigated. Our approach is based on a Ginzburg--Landau theory for…
For future on-chip communication schemes, it is essential to integrate nanoscale materials with an ultrafast optoelectronic functionality into high-frequency circuits. The atomically thin graphene has been widely demonstrated to be suitable…
Thermal conductivity of aligned polymer molecules can be exceptionally high along the alignment direction due to energy transport through strong covalent bonds. At the same time, it is highly sensitive to molecular conformation, varying by…
The emergence of twistronics provides an unprecedented platform to modulate the band structure, resulting in exotic electronic phenomena ranging from ferromagnetism to superconductivity. However, such concept on phonon engineering is still…
We report temperature evolution of coherently excited acoustic and optical phonon dynamics in superconducting iron pnictide single crystal Ca(Fe_0.944Co_0.056)_2As_2 across the spin density wave transition at T_SDW ~ 85 K and…
Phononic integrated circuits, which manipulate GHz-frequency acoustic fields in {\mu}m-scale waveguides, provide new degrees of freedom for routing and manipulation of microwaves in deeply sub-wavelength geometries with associated…
Nonlinear phononics is the phenomenon in which a coherent dynamics in a material along a set of phonons is launched after its infrared-active phonons are selectively excited using external light pulses. The microscopic mechanism underlying…