Recent Progress in Advanced Materials for Photonics and Energy Applications

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Third harmonic generation in LiKB4O7 single crystal

The third order nonlinear optical properties of the lithium potassium borate (LiKB4O7) single crystal have been investigated by means of the rotational Maker fringe technique using Nd:YAG laser at 1064 nm working in picosecond regime. The value of the third order nonlinear optical susceptibility was calculated using the theoretical model of Kajzar et al. and was found to be about 1.4 × 10−21 m2 V−2 that is one order higher than that of fused silica

Scaling of the electron dissipation range of solar wind turbulence

Electron scale solar wind turbulence has attracted great interest in recent years. Clear evidences have been given from the Cluster data that turbulence is not fully dissipated near the proton scale but continues cascading down to the electron scales. However, the scaling of the energy spectra as well as the nature of the plasma modes involved at those small scales are still not fully determined. Here we survey 10 years of the Cluster search-coil magnetometer (SCM) waveforms measured in the solar wind and perform a statistical study of the magnetic energy spectra in the frequency range [$1, 180$]Hz. We show that a large fraction of the spectra exhibit clear breakpoints near the electon gyroscale $\rho_e$, followed by steeper power-law like spectra. We show that the scaling below the electron breakpoint cannot be determined unambiguously due to instrumental limitations that will be discussed in detail. We compare our results to recent ones reported in other studies and discuss their implication on the physical mechanisms and the theoretical modeling of energy dissipation in the SW.Comment: 10 pages, submitte

Second and third-order nonlinear optical behavior of natural pigment: chlorophyll and crocin

To provide an insight into the microscopic second and third-order nonlinear optical (NLO) behavior of chlorophyll a and crocin, we have computed the electric dipole moments (μ), dispersion-free first hyperpolarizabilities (β), frequency-dependent first and second (γ) hyperpolarizabilities at 1064 nm wavelength area using time-dependent Hartree-Fock (TDHF) method. According to ab-initio calculation results, the examined compounds exhibit first and second hyperpolarizabilities with non-zero values, implying second and third-order NLO phenomena

Theoretical calculations of second and third-order nonlinear susceptibilities and their corresponding hyperpolarizabilities of a styrylquinolinium dye

The second (Xexp(2)) and third-order (Xexp(3)) susceptibilities of a styrylquinolinium dye (1) have been determined utilizing second-harmonic generation (SHG) and third-harmonic generation (THG) techniques, respectively. The reported measurement findings on Xexp(2) and Xexp(3) have been compared with the theoretical data evaluated here by means of ab-initio quantum mechanical calculations. The electric dipole moments (μ), static dipole polarizabilities (a) and first hyperpolarizabilities (β) have been computed by density functional theory (DFT) at B3LYP/6-311+G(d, p) level. To reveal the frequency-dependent second and third-order microscopic nonlinear optical (NLO) behavior of the title compound, the dynamic dipole polarizabilities, first and second (γ) hyperpolarizabilities have been theoretically investigated using time-dependent Hartree-Fock (TDHF) method. According to the experimental and theoretical results, the values of susceptibilities and the corresponding microscopic coefficients with large non-zero responses make the examined dye promising candidate for NLO applications

Computational studies on linear, second and third-order nonlinear optical properties of novel styrylquinolinium dyes

The electric dipole moments (μ), static dipole polarizabilities (α) and first hyperpolarizabilities (β) of styrylquinolinium dyes, D8 and D21, have been computed by density functional theory (DFT). The one-photon absorption (OPA) characterizations have been investigated using UV–vis spectroscopy and further interpreted using computational chemistry. The time-dependent Hartree–Fock (TDHF) method has been used to describe the dynamic dipole polarizabilities, dynamic second-order and also static and dynamic third-order nonlinear optical (NLO) properties. D8–D21 have rather high β and second hyperpolarizabilities (γ). The highest occupied molecular orbitals (HOMO), the lowest unoccupied molecular orbitals (LUMO) and the HOMO–LUMO band gaps for D8–D21 have been evaluated by DFT