The transition strengths for the four infrared-active vibrations of charged C60 molecules are evaluated in self-consistent density functional theory using the local density approximation. The oscillator strengths for the second and fourth modes are strongly enhanced relative to the neutral C60 molecule, in good agreement with the experimental observation of “giant resonances” for those two mode...

We provide here experimental data on the phonon density-of-states of MgB2 obtained by the inelastic neutron scattering technique. The measurements were performed for the natural boron-based magnesium diboride with use of a time-of-flight neutron spectrometer. Several phonon bands were observed in the phonon spectrum at energies of about 33, 55, 82 and 99 meV. We show that the cutoff energy of t...

a theory is presented for the dispersion relations of the nonlinear phonon-polaritons arising when phonons are coupled to the electromagnetic waves in multilayered structures of nonlinear materials. the calculations are applied to a multilayered structure consisting of a thin film surrounded by semi-infinite bounding media where each layer may have a frequency dependent dielectric function and ...

Double-γ vibrations in deformed nuclei are studied in the context of the interacting boson model with special reference to their anharmonic character. It is shown that large anharmonicities can be obtained with interactions that are (at least) of three-body nature between the bosons. As an example the γ vibrations of the nucleus 166 68Er98 are studied in detail. Typeset using REVTEX 1 Nuclear q...

Since the discovery of the high Tc superconductivity by Bednorz and Muller, several workers around the world have studied several systems to reach a really high Tc superconductor. As the strong electron-phonon coupling may be one of the possible origins of the high Tc, a knowledge about the phonon in these materials is essential. In order to investigate phonon spectra, Raman and infrared spectr...

Excitonic effects underpin the fascinating optoelectronic properties of 2D perovskites that are highly favorable for photovoltaics and light-emitting devices. Analogous to switching in transistors, manipulating these excitonic using coherent phonons could unlock new applications. Presently, a detailed understanding this underlying mechanism remains modest. Herein, origins carrier-phonon couplin...

Dynamical backaction resulting from radiation pressure forces in optomechanical systems has proven to be a versatile tool for manipulating mechanical vibrations. Notably, dynamical resulted the cooling of resonator its ground-state, driving phonon lasing, generation entangled states, and observation optical-spring effect. In certain magnetic materials, vibrations can interact with excitations (...

The vibron dynamics associated to amide-I vibrations in a 3D α-helix is described according to a generalized Davydov model. The helix is modeled by three spines of hydrogen-bonded peptide units linked via covalent bonds. To remove the intramolecular anharmonicity of each amide-I mode and to renormalized the vibron-phonon coupling, two unitary transformation have been applied to reach the dresse...