N ov 1 99 8 Calculations of the A 1 phonon frequency in photoexcited
نویسندگان
چکیده
Calculations of the A 1 phonon frequency in photoexcited tellurium are presented. The phonon frequency as a function of photoexcited carrier density and phonon amplitude is determined. Recent pump probe experiments are interpreted in the light of these calculatons. It is proposed that, in conjunction with measurements of the phonon period in ultra-fast pump-probe reflectivity experiments, the calculated frequency shifts can be used to infer the evolution of the density of photoexcited carriers on a sub-picosecond timescale .
منابع مشابه
Investigation of phononic, dynamic and thermal properties of indium nitride in different phases
In this paper, the phonon, dynamic and thermal properties of indium nitride in two phases are investigated. The calculations are performed using the pseudopotantial method in the framework of density functional theory and by using the quantum-espresso Package. In the calculations, the exchange-correlation terms of LDA, GGA and PBE0 approximation are used. Investigation of phononic properties s...
متن کاملTheory of Nonlinear s-Polarized Phonon-Polaritons in Multilayered Structures
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 ...
متن کاملar X iv : c on d - m at / 9 81 13 81 v 1 2 6 N ov 1 99 8 Longitudinal and transverse forces on a vortex in superfluid 4 He
We examine the transverse and longitudinal components of the drag force upon a vortex filament due to the scattering of liquid 4He excitations. For this purpose, we consider a recently proposed Hamiltonian that describes the dissipative motion of a vortex, giving an explicit expression for the vortexquasiparticle interaction. The involved dissipative coefficients are obtained in terms of the re...
متن کاملar X iv : n uc l - th / 9 71 10 27 v 1 1 3 N ov 1 99 7 Shell - model calculations for the three - nucleon system
We use Faddeev’s decomposition to solve the shell-model problem for three nucleons. The dependence on harmonic-oscillator excitations allowed in the model space, up to 32h̄Ω in the present calculations, and on the harmonicoscillator frequency is studied. Effective interactions derived from Nijmegen II and Reid93 potentials are used in the calculations. The binding energies obtained are close to ...
متن کاملCoherent phonon coupling to individual Bloch states in photoexcited bismuth.
We investigate the temporal evolution of the electronic states at the bismuth (111) surface by means of time- and angle-resolved photoelectron spectroscopy. The binding energy of bulklike bands oscillates with the frequency of the A(1g) phonon mode, whereas surface states are insensitive to the coherent displacement of the lattice. A strong dependence of the oscillation amplitude on the electro...
متن کامل