相关论文: Nonlinear phononics in Bi$_2$Te$_3$ nanoscale thin…
We discuss the mechanism of coherent phonon generation by Stimulated Ionic Raman Scattering, a process different from conventional excitation with near visible optical pulses. Ionic Raman scattering is driven by anharmonic coupling between…
Phonon spectra of CdSe nanoplatelets (2-6 ML) with the zinc-blende structure were calculated from first principles within the density-functional theory. It turned out that the Lamb modes in nanoplatelets are in fact optical rather than…
The thermal properties of solids under nanoscale confinement are currently not understood at the atomic level. Recent numerical studies have highlighted the presence of a minimum in the thermal conductivity as a function of thickness for…
Raman spectroscopy has become an essential technique to characterize and investigate graphene and many other two-dimensional materials. However, there still lacks consensus on the Raman signature and phonon dispersion of atomically thin…
Nanophononics has the potential for information transfer, in an analogous manner to its photonic and electronic counterparts. The adoption of phononic systems has been limited, due to difficulties associated with the generation,…
We investigate the dynamics of single- and multi-photon emission from detuned strongly coupled systems based on the quantum-dot-photonic-crystal resonator platform. Transmitting light through such systems can generate a range of…
We report ab-initio calculations of the phonon dispersion relations of the single-layer and bulk dichalcogenides MoS2 and WS2. We explore in detail the behavior of the Raman active modes, A1g and E2g as a function of the number of layers.…
First-principles phonon calculations along with Kohn-Sham density functional theory (DFT) is an essential tool to study the lattice dynamics, thermodynamical properties and phase-transitions of materials. The two full-Heusler compounds…
As an alternative to atomistic calculations of long-wavelength acoustic modes of atomically thin layers, which are known to converge very slowly, we propose a quantitatively predictive and physically intuitive approach based on continuum…
Phonon measurements in the A15-type superconductors were complicated in the past because of the unavailability of large single crystals for inelastic neutron scattering, e.g., in the case of Nb$_3$Sn, or unfavorable neutron scattering…
The coherent nonlinear dynamics between collective excitations, such as magnons and phonons, drive emergent phenomena in quantum materials, yet their direct observation remains a central challenge. Here, using double-terahertz-pump…
Long-living coupled transverse and longitudinal phonon modes are explored in dense and regular arrangements of flat microfluidic droplets. The collective oscillations are driven by hydrodynamic interactions between the confined droplets and…
We explore the ultrafast reflectivity response from photo-generated coupled phonon-surface Dirac plasmons in Sb$_2$Te$_3$ topological insulators several quintuple layers thick. The transient coherent phonon spectra obtained at different…
Starting from Newton's equations of motion, we derive a dynamical density functional theory (DDFT) applicable to atomic liquids. The theory has the feature that it requires as input the Helmholtz free energy functional from equilibrium…
Layered two-dimensional (2D) materials have highly anisotropic thermal properties between the in-plane and cross-plane directions. In general, it is thought that cross-plane thermal conductivities ($\kappa_z$) are low, and therefore c-axis…
The transmission of acoustic phonons is an important element in the design and performance of nano-mechanical devices operating in the mesoscopic limit. Analytic expressions for the power transmission coefficient, T, exist only in the…
Nanostructured semiconducting materials are promising candidates for thermoelectrics due to their potential to suppress phonon transport while preserving electrical properties. Modeling phonon-boundary scattering in complex geometries is…
We propose a theoretical framework for the detection of order parameter fluctuations in three dimensions using ultrafast coherent phonon spectroscopy. We focus our attention on long wavelength charge density fluctuations (plasmons), and…
Resonant Raman spectroscopy is realized on closely spaced nanowire based quantum wells. Phonon quantization consistent with 2.4 nm thick quantum wells is observed, in agreement with cross-section transmission electron microscopy…
We combine polarization-resolved low frequency Raman microscopy and dispersion-corrected density-functional calculations (DFT-D3) to study polymorph-dependent lattice vibrations in coronene, a model molecular system for nanographenes and…