Electromagnetically induced transparency is predicted for x rays in laser-dressed neon gas. The x-ray photoabsorption cross section and polarizability near the Ne K edge are calculated using an ab initio theory suitable for optical strong-field problems. The laser wavelength is tuned close to the transition between 1s(-1)3s and 1s(-1)3p approximately 800 nm). The minimum laser intensity require...

We report about the observation of influence of the light polarization on the photocrystallization process in the Se Ag I , elementary Se and Se Te films. Irradiation with linearly polarized He–Ne and Arq laser light results in the 70 15 15 80 20 Ž . formation of polycrystalline films with strong optical anisotropy dichroism , the sign of which is determined by the direction of the electrical v...

This paper deals with the study of the spectral components of Lamb waves generated in thin aluminium plate using pulsed Nd-YAG laser and detected using a He-Ne Laser Heterodyne interferometer. Laser generation of Lamb waves leads to simultaneous generation of various frequency component as well as multiple Lamb wave modes. The Lamb wave signals are successfully and comprehensively analyzed usin...

We demonstrate the generation of an intense soft-x-ray-laser beam by saturated amplification of high harmonic seed pulses in a dense transient collisional soft-x-ray-laser plasma amplifier created by heating a titanium target. Amplification in the 32.6 nm line of Ne-like Ti generates laser pulses of subpicosecond duration that are measured to approach full spatial coherence. The peak spectral b...

We describe first the single mode output intensity of a Brewster windowed laser containing isotope mixtures when the cavity tuning is varied, and then the single mode output of a non-Brewster windowed laser under the influence of an axial magnetic field (Zeeman laser). We show how the central tuning (Lamb) dip in intensity gives way to more complicated tuning dependences such as a double dip. F...

One of the solutions of the Helmholtz equation is the vortex beams. In the recent decades, production and applications of these types of beams have found serious attentions. Determination of the vortex beam topological charge and its sign are very important issues. Odd number of reflections of the vortex beam changes its vorticity. In this paper, we have used a q-plate to generate a vortex beam...

In this paper, the status of the Laser-Plasma Accelerator field within the Advanced Accelerator Concepts area of research is reviewed. In particular, I review the status of the Plasma Beat Wave Acceleration (PBWA) scheme, the SelfModulated, Laser-Wake Field Acceleration (SMLWFA) scheme and the Laser-Wake Field Acceleration (LWFA) scheme. In all these three schemes, charged particles are acceler...

H. M. Shang National University of Singapore Department of Mechanical Engineering 10 Kent Ridge Crescent 119260 Singapore Abstract. We have developed a measurement method to evaluate deformation of a metallic membrane (thickness 2 mm) in a micro-radiofrequency switch. The method is based on a modified Michelson interferometer incorporated with optoelectronic devices including a He-Ne laser, con...

The application of He-Ne laser technologies for description of articular cartilage degeneration, one of the most common diseases worldwide, is an innovative usage of these technologies used primarily in material engineering. Plain radiography and magnetic resonance imaging are insufficient to allow the early assessment of the disease. As surface roughness of articular cartilage is an important ...