The interference minimum in the molecular high-order harmonic generation is studied by numerically solving the non-Born-Oppenheimer approximation time-dependent Schrödinger equation. The results show that two kinds of interference minima appear in the high-order harmonic spectrum when the hydrogen molecular ion is exposed to the laser pulse. Furthermore, by adjusting wavelength of the laser as ...

Recently, power quality (PQ) has because a significant issue for both power supplies and customers. Researchers in all developed countries know that power quality is one of the factors of losses in the network. Increasing power electronic equipment changes current waveform in distribution networks and this can cause many problems in networks. Distortion of voltage waveforms results in the appea...

OBJECTIVE Power line interference may severely corrupt neural recordings at 50/60 Hz and harmonic frequencies. The interference is usually non-stationary and can vary in frequency, amplitude and phase. To retrieve the gamma-band oscillations at the contaminated frequencies, it is desired to remove the interference without compromising the actual neural signals at the interference frequency band...

We carry out wavelength-dependent second harmonic interference experiments using thin films of an organic dye as nonlinear optical sources. While the measured difference of refractive index between the fundamental and second harmonic wavelengths follows the theoretical expectation for air in a wide spectral region, anomalous dispersion is observed when the second harmonic light lies in the abso...

We demonstrate a new method to investigate the origin of spectral structures in high-harmonic generation. We report detailed measurements of high-harmonic spectra in aligned nitrogen and carbon dioxide molecules. Varying the wavelength and intensity of the generating laser field, we show that the minimum in aligned N2 molecules is nearly unaffected, whereas the minimum in aligned CO2 molecules ...

Experimental evidence of scattering of second-harmonic light from the surface of spherical particles of optical dimensions is presented. This mechanism for second-harmonic generation is observed in a suspension of monodisperse spherical colloidal particles, ordered in a centrosymmetric crystalline lattice. In this periodic structure the mechanism of phase matching is provided by the bending of ...

A constrained iterative method for harmonic source parameter estimation is proposed based on an EM algorithm with an intent for harmonic source separation. The problem of coinciding partials and interference among them in general is mitigated by the constraints on the “weak” partials on the stronger ones of the same harmonic source. A useful scheme to determine the weakness of a partial is prop...

We study the evolution inside a harmonic trap of Bose-Einstein condensates released from the periodic potential of an optical lattice. After a time-of-flight, harmonic motion of the interference peaks is observed as well as a breathing motion in the direction perpendicular to the optical lattice. We interpret these results in terms of a simple physical model and discuss the possibility of more ...