Study of intensity-dependent nonlinear optical coefficients of GaP optical crystal at 800 nm by femtosecond pump-probe experiment

The intensity-dependent two-photon absorption and nonlinear refraction coefficients of GaP optical crystal at 800 nm were measured with time-resolved femtosecond pump-probe technique. A nonlinear refraction coefficient of 1.7*10^(-17) m2/W and a two-photon absorption coefficient of 1.5*10^(-12) m/W of GaP crystal were obtained at a pump intensity of 3.5*10^(12) W/m2. The nonlinear refraction coefficient saturates at 3.5*10^(12) W/m2, while the two-photon absorption coefficient keeps linear increase at 6*10^(12) W/m2. Furthermore, fifth-order nonlinear refraction of the GaP optical crystal was revealed to occur above pump intensity of 3.5*10^(12) W/m2.

Distinguishing the sources of Asian dust based on electron spin resonance signal intensity and crystallinity of quartz

IEECAS SKLLQG

Summer monsoon intensity controls C-4/C-3 plant abundance during the last 35 ka in the Chinese Loess Plateau: Carbon isotope evidence from bulk organic matter and individual leaf waxes

IEECAS SKLLQG

The coulomb potential energy effect on the intensity of the characteristic lines at highly charged ion incendence on Al surface

The Al atomic characteristic spectral lines were induced by the impact of Ar-40(q+) ions (8 <= q <= 16; kinetic energy 150 keV) on Al surface. The result shows that by Penning impinging and resonant capture, the ion energy is deposited on the Al surface to excite the target atom, which is different from light excitation. Not only are the transitions betweem electronic configurations of the atomic complex excited, but the enhancing tendency of the characteristic spectral line intensity is consistent with the enhancing tendency of the coulomb potential energy of the incident ions with increasing charged states.

Control of chemical reaction in high-intensity laser field

The prospects of control chemical reaction in high-intensity laser field are talked about here, and some experimental and theoretical designs are reviewed and discussed also.

Optical intensity gradient by colloidal photonic crystals with a graded thickness distribution

Gradient colloidal crystals with a thickness gradient were prepared by the vertical deposition technique with vertically graded concentration suspensions. The thickness of the gradient colloidal crystal gradually changes at different positions along the specific gradient direction of the crystal. The thickness gradient was determined by the concentration gradient, depending on the initial colloidal concentration and the settling time. The optical transmission intensity at the dip wavelength can be tuned by changing the thickness of the colloidal crystals. The gradient colloidal crystals lead to a gradient of optical intensity at the dip in transmission light. The gradient of optical intensity at the dip increases as the thickness gradient of the colloidal crystal increases.

Intensity exaggeration of endohedral metallofullerenes in laser-desorption-ionization time-of-flight mass spectrometry

The laser-desorption-ionization time-of-flight mass spectrometry and desorption-electron-ionization mass spectrometry were employed for the characterization of metallofullerenes extract. it was found that the relative intensities of metallofullerenes in this positive-ion, negative-ion LD-TOF MS and DEI MS were much different. This phenomenon should have relationship with the peculiar ionization energies and electron affinities of metallofullerenes.

EFFECT OF THE CONCENTRATION OF THE ER3+ ION ON THE SPECTRAL INTENSITY PARAMETERS OF ER-YAG CRYSTALS

The absorption spectra of Er:YAG (YAG, yttrium-aluminium-garnet) crystals containing different concentrations of the trivalent erbium ion were measured and the spectral intensity parameters were calculated from these experimental spectra using the Judd-Ofelt model. The results indicate that the phenomenological intensity parameters, OMEGA(lambda) (lambda = 2, 4 and 6), vary as a function of the concentration of the Er3+ ion in the Er:YAG crystal, but no variation in the fluorescence-branching ratios as a function of the concentration of the Er3+ ion is found. An empirical formula is proposed to describe the relationship between the spectral intensity parameters and the Er3+ ion concentration in the Er:YAG crystal. The spectral intensity parameters exhibit a maximum in Er:YAG crystals containing about 1-1.5 at.% Er3+ ion. The effect of the Er3+ ion concentration on the spectral intensity parameters may be attributed to the inhomogeneous lattice distortion in the cell of the Er:YAG crystal caused by the dopant erbium ions.