Recently, Dammak and coworkers (Phys. Rev. Lett. 103:190601, 2009) proposed that the quantum statistics of vibrations in condensed systems at low temperature could be simulated by running molecular dynamics simulations in the presence of a colored noise with an appropriate power spectral density. In the present contribution, we show how this method can be implemented in a flexible manner and at...

Expressions are derived for the vibrational second hyperpolarizability 1'" of SF 6' in the static limit and for the nonlinear-optical processes of the dc Kerr effect, electric-field-induced second harmonic generation (ESHO), and third harmonic generation (THO). These expressions give 1'" in terms of vibrational transition dipole, polarizability, and first hyperpolarizability matrix elements (f-...

A theoretical investigation is presented that examines the wavelength scaling from near-visible (0.8 micro m) to midinfrared (2 micro m) of the photoelectron distribution and high harmonics generated by a "single" atom in an intense electromagnetic field. The calculations use a numerical solution of the time-dependent Schrödinger equation (TDSE) in argon and the strong-field approximation in he...

We study numerically low-order harmonic generation in noble gases pumped by intense femtosecond laser pulses in the tunneling ionization regime. We analyze the influence of the phase-mismatching on this process, caused by the generated plasma, and study in dependence on the pump intensity the origin of harmonic generation arising either from the bound-electron nonlinearity or the tunnel-ionizat...

We present a theoretical investigation of high-order harmonic generation in a chirped two-colour laser field, which is synthesized by an 800 nm fundamental chirped pulse and a 1200 nm subharmonic chirped pulse. With the introduction of a polarization angle, both the harmonic cutoff is significantly extended and the spectrum intensity is effectively enhanced compared with the orthogonally polari...

This paper presents accurate solutions for nonlinear transcendental equations of the selective harmonic elimination technique used in three-phase PWM inverters feeding the induction motor by particle swarm optimization (PSO). With the proposed approach, the required switching angles are computed efficiently to eliminate low order harmonics up to the 23 from the inverter voltage waveform, wherea...

The nonlinear optical properties of coumarin 343 (C343) dye-attached TiO2 nanoparticles in the size range 5–8 nm adsorbed at the interface of water/1,2-dichloroethane have been studied by using the surface second harmonic generation technique. No second harmonic (SH) response was observed from the bare TiO2 nanoparticles adsorbed at the interface, however, a strong SH response was measured from...

O. A. Teplov developed an approach to describe the meson quark model by establishing a mathematical series (harmonic series). With respect physical mesons, he made some basic hypotheses of his own and used well-known theory harmonic oscillation construct numerical mass that obeys rigid multiplicative pattern allows masses be calculated accurately. We have found series, i.e., their masses, has f...

a direct conversion modulator-demodulator with even harmonic mixers with emphasis on noise analysis is presented. the circuits consist of even harmonic mixers (ehms) realized with antiparallel diode pairs (apdps). we evaluate the different levels of i/q imbalances and dc offsets and use signal space concepts to analyze the bit error rate (ber) of the proposed transceiver using m-ary qam schemes...