The Cerenkov free electron laser (CFEL) model under consideration consists of a pre-bunched relativistic electron beam and a dielectric loaded waveguide. The increase in the growth rate and gain with the change in phase by using a pre-bunched electron beam in a Cerenkov free electron laser (CFEL) has been studied. The growth rate and gain is calculated at experimentally known CFEL and FEL param...

A low diffraction beam is obtained by altering the existing resonator of a CO2 laser using a special phase plate. The phase plate is designed based on the boundary diffraction principle and is implemented on the resonator rear mirror. It is found that the low diffraction beam has a smaller M 2 value than that of a Gaussian beam. The effects of the improved beam quality on a laser ablation proce...

The output beam quality of multi transverse modes of laser, are relatively poor. In order to obtain better beam quality, one may use an aperture inside the laser resonator. In this case, various transverse modes can be selected. We have selected various transverse modes both by simulation and doing experiment. By inserting a circular aperture inside the diode end-pumped Nd:YAG pulsed laser reso...

A single-beam interference-lithography scheme is demonstrated for the fabrication of large-area slant gratings, which requires exposure of the photoresist thin film spin-coated on a glass plate with polished side-walls to a single laser beam in the ultraviolet and requires small coherence length of the laser. No additional beam splitting scheme and no adjustments for laser-beam overlapping and ...

Multimode laser operation is usually characterized by high output power, yet its beam quality is inferior to that of a laser with single TEM00 mode operation. Here we present an efficient approach for improving the beam quality of multimode laser resonators. The approach is based on splitting the intra-cavity multimode beam into an array of smaller beams, each with a high quality beam distribut...

Cilex-Apollon is a high intensity laser facility delivering at least 5 PW pulses on targets at one shot per minute, to study physics such as laser plasma electron or ion accelerator and laser plasma X-Ray sources. Under construction, Apollon is a four beam laser installation with two target areas. To control the laser beam characteristics and alignment, more than 75 CCD cameras and 100 motors a...

We are developing Laser Super Cavity for compact X-ray generator based on Inverse Compton Scattering with several tens MeV electron beam. The laser supercavity increases the laser power and makes small laser beam size at the collision point with the electron beam. A FabryPerot cavity as the laser supercavity has been tested at the KEK-ATF (Accelerator Test Facility) and the design for the incre...

We studied proton beam production from a laser ion source using hydrogen rich target materials. In general, gas based species are not suitable for laser ion sources since formation of a dense laser target is difficult. In order to achieve reliable operation, we tested hydride targets using a sub nanosecond Q-switched Nd-YAG laser, which may help suppress target material consumption. We detected...

We report on the first laser cooling of a bunched beam of multiply charged C ions performed at the ESR (GSI) at a beam energy of E = 1.47GeV. Moderate bunching provided a force counteracting the decelerating laser force of one counterpropagating laser beam. This versatile type of laser cooling lead to longitudinally space-charge dominated beams with an unprecedented momentum spread of ∆p/p ≈ 10...