introduction: the unprotected eye is extremely sensitive to laser radiation and can be permanently damaged from direct or reflected beams. the area of the eye damaged by laser energy is dependent upon the wavelength of the incident laser beam, duration of exposure and tissue characteristics. this study aims to investigate the effect of intense green light from doubled frequency neodymium-doped ...

In this review we consider three important applications of lasers in high energy physics: γγ, γe colliders, laser cooling, positron production. These topics are actual now due to plans of construction linear ee, ee, γγ, γe colliders with energies 0.3–1 TeV. High energy photons for γγ, γe collisions can be obtained using laser backscattering. These types of collisions considerably increase physi...

In high-order harmonic generation by an intense laser, intrinsic phases can develop at the atomic level between the laser field and the individual emitted harmonics. Because intrinsic phases can vary rapidly with the laser intensity, they can strongly influence phase matching to the extent that the laser intensity varies within the generating medium. Previously reported measurements of broad fa...

Highly collimated MeV electron beam guiding has been observed along the target surface following the interaction of bulk target irradiation by femtosecond laser pulses at relativistic intensities. The beam quality is shown to depend critically on the laser contrast: With a ns prepulse, the generated electron beam is well concentrated and intense, while a high laser contrast produces divergent e...

Recent experiments [1,2] at the Experimental Storage Ring (ESR) at GSI have shown that relativistic Li-like carbon (C) ion beams can be laser-cooled to an unprecedented momentum spread of p/p 10. Here, a single-frequency laser was tuned to the Doppler-shifted 1s2s 1s2p (P1/2 and P3/2) transitions. These results encourage the application of laser cooling to beams of other Liand Na-like ions at e...

The ECLISSE experiment proved in 2002 the possibility to couple a Laser Ion Source (LIS) with an Electron Cyclotron Resonance Ion Source (ECRIS) in order to obtain ion beams from refractory metals with a cw beam structure. The use of a LIS inside the ECRIS plasma chamber may permit to increase the beam current and the ion charge state. The use of 3 generation ECRIS may extend the capabilities o...

In this paper, we have reported the fabrication of two-dimensional photonic crystals, using a direct writing method in azo polymers. Periodic structures have been fabricated using the interference patterns of two coherent laser beams. The frequency response of the initial one-dimensional structure shows an attenuation of 19.3dB at 1554nm. The twodimensional structure shows 8.3dB and 11.3dB of a...

We have successfully generated vector beams with higher-order polarization states using photonic-crystal lasers. We have analyzed and designed lattice structures that provide cavity modes with different symmetries. Fabricated devices based on these lattice structures produced doughnut-shaped vector beams, with symmetries corresponding to the cavity modes. Our study enables the systematic analys...

the drawing of frequency-path (f-p) models of optical beams is an approach for nonlinearity analysis in nano-metrology systems and sensors based on the laser interferometers. in this paper, the frequency-path models of four nano-metrology laser interferometry systems are designed, analyzed and simulated, including conventional and modified two- and three-longitudinal-mode laser interferometers....

We describe an optical beam converter for an efficient transformation of Gaussian femtosecond laser beams to single- or double-charge vortex beams. The device achieves a conversion efficiency of 75% for single- and 50% for double-charge vortex beams and can operate with high-energy broad bandwidth pulses. We also show that the topological charge of a femtosecond vortex beam can be determined by...