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In this paper, conception and practical realization of single frequency, widely tuneable Nd:YVO4/YVO4/KTP microchip laser operation at 532 nm is presented. Theoretical analysis of the single mode operation of such laser configuration is introduced. The single frequency operation was obtained in birefringent filter configuration where YVO4 beam displacer acts like ideal polarizer. We obtain stable...
The lasing modes in the arbitrarily shaped active microcavity are considered as solutions to the 2-D linear eigenproblem for the Maxwell equations with exact boundary and radiation conditions. This problem can be reduced to the set of two coupled boundary integral equations with smooth or integrable kernels. Discrete form of these equations is built using the Nystrom-type algorithm and corresponding...
Recently ferrofluids and magnetic nanofluids have attracted considerable attention as they are considered for a large variety of applications which require fluidic and magnetic properties simultaneously. Such liquid media are in principle easily controllable e.g. by a magnetic field and their flow and properties can be altered in a controllable way. In the case of iron nanoparticles, these can exhibit...
Simultaneously measurements of the second harmonic generation (SHG) signals in the forward and backward directions from deep shade plants were achieved. These measurements show that the deep shade plants produce high SHG signal in both directions and the SHG signals strongly depend on the state of the polarization of the laser light and the orientation of the dipole moment in the molecules that interact...
A generalization of the I-scan method is considered by using one, two, three and four waves mixing experiments inside a 4-f imaging system for nonlinear optical measurements. By placing the material at the focus, the sensitivities of the measurements are compared systematically showing the same order of magnitude for all the studied configurations. Moreover the determination of the cubic optical nonlinearity...
Noise performance of parametric amplifiers is typically calculated assuming un-depleted operation. However, in many applications especially when applied as regenerative amplifiers in systems based on phase shift keyed modulation schemes, this assumption is not valid. Here we show the impact on accumulated spontaneous emission for a parametric amplifier operated in saturation.
In this paper we present results of the numerical modelling of the temperature distribution in a GaAs-based, continuously optically pumped Vertical-External-Cavity Surface-Emitting-Laser, emitting at about 980 nm. Effectiveness of different methods of the temperature reduction in the active region, such as substrate thinning and using a heat spreader, is presented and compared.
We investigate two generic conceptual ideas to obtain bulk 3D negative index metamaterials, which exhibit isotropic properties. One design is a traditional design of 3D wires ended with metallic plates. Another design is based on the nested structures approach, when one element providing magnetic response is inserted into another design with negative dielectric constant. Both constitutive elements...
Surface photonic mode propagation is shown to be possible at the cut of metal layers by a perpendicular plane. Solutions for the amplitude distribution revealing the surface mode transformation to slab modes and edge modes are presented together with scaling experiments in microwave range. Optical applications (of nanometer-scale multiple layers) are discussed.
Computational aspects of the parabolic equation method are discussed: transparent boundary conditions for straight and bent Bragg waveguides, 3D finite-difference scheme in polar coordinates, estimation of radiation losses and fundamental mode stabilization.
Parabolic pulses in optical fibers have stimulated an increasing number of applications. We review here the physics underlying the generation of such self-similar pulses as well as the results obtained in a wide-range of passive or active experimental configurations.
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