We have constructed an atom interferometer of the Mach-Zehnder type, operating with a thermal lithium beam. Atom diffraction uses Bragg diffraction on laser standing waves. With first order diffraction, our apparatus has given a large signal and a very good fringe contrast (74%), which we believe to be the highest ever observed with atom interferometers. This apparatus will be applied to high s...

Modified volume Fresnel zone plates (MVFZPs) fabricated with laser direct writing were optimized for higher diffraction efficiencies. The Fresnel radii in each layer of a volume zone plate were iteratively adjusted by a simulation-based direct search optimization. The results show that optimization is effective but depends strongly on the starting diffraction efficiencies determined by the MVFZ...

Laser wakefield accelerators can produce electric fields of order 10–100 GV/m, suitable for acceleration of electrons to relativistic energies. The wakefields are excited by a relativistically intense laser pulse propagating through a plasma and have a phase velocity determined by the group velocity of the light pulse. Two important effects that can limit the acceleration distance and hence the...

Molecular structure is usually determined by measuring the diffraction pattern the molecule impresses on x-rays or electrons. We used a laser field to extract electrons from the molecule itself, accelerate them, and in some cases force them to recollide with and diffract from the parent ion, all within a fraction of a laser period. Here, we show that the momentum distribution of the extracted e...

A fundamental limit to existing optical techniques for measurement and manipulation of spin degrees of freedom is set by diffraction, which does not allow spins separated by less than about a quarter of a micrometre to be resolved using conventional far-field optics. Here, we report an efficient far-field optical technique that overcomes the limiting role of diffraction, allowing individual ele...

Natural resources in general and plant materials in particular are receiving more attention due to their safety as pharmaceutical excipients. Present work assessed the potential of a natural polysaccharide, pectin to mask the bitter taste of ambroxol hydrochloride, by microencapsulation technique, and its possibility to formulate as a fast disintegrating dosage form. Taste masking is an importa...

A tunable external-cavity diode laser (ECDL) based on a transmission diffraction grating in a Littrow mount has been developed and characterized. A single-transverse-mode diode laser at 650 nm is used in an external-cavity configuration in which the transmission grating is used as a dispersive element to select the single longitudinal mode. The transmission diffraction grating is made with elec...

We report the first experimental demonstration of longitudinal compression of laser-accelerated electron pulses. Accelerated by a femtosecond laser pulse with an intensity of 10¹⁸ W/cm², an electron pulse with an energy of around 350 keV and a relative momentum spread of about 10⁻² was compressed to a 500-fs pulse at a distance of about 50 cm from the electron source by using a magnetic pulse c...

High-accuracy dimensional measurements by laser interferometers require corrections because of diffraction, which makes the effective fringe-period different from the wavelength of a plane (or spherical) wave λ0. By using a combined X-ray and optical interferometer as a tool to investigate diffraction across a laser beam, we observed wavelength variations as large as 10-8λ...