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In this study, a light-driven deformable mirror is fabricated by electron beam lithography. The mirror is consisted of a deformation layer and a micromirror array. The deformation layer is made of an azobenzene polymer and the micromirro array is deposited on the deformation layer. The deformation of azobenzene polymer is induced by illuminating a continuum wave beam or femto-second pulse laser beam. Then, the micromirror is displaced. The displacement modulation is experimentally confirmed by interference measurement.

This paper proposes a method to increase the recording density of binary data pages in holographic memory. The recording density is increased by decreasing the rectangular aperture size on a Fourier plane. To extract the original data page from the low quality image, a four-step phase mask is designed. The principle of the proposed method is numerically verified.

Multi-valued phase patterns were multiply recorded by retardagraphy in order to improve recording density and data transfer rate. In the experiment, the phase pattern consists of four values were recorded on a polarization-sensitive medium by focusing the recording beam, and three patterns were multiply recorded by shifting the focal point. The recorded patterns could be independently reconstructed.

Interaction of an ultra-short intense laser pulses with thin foil targets is accompanied by acceleration of ions from the target surface. To make this ion source suitable for applications, it is of particular importance to increase the efficiency of laser energy transformation into accelerated ions and the maximum ion energy. This can be achieved by using thin foil target with a layer of microscopic spheres on the front, laser irradiated surface. The influence of microscopic structure on the target surface on the laser target interaction and subsequent ion acceleration is studied here using numerical simulations. The influence of the size of microspheres, the density profile and the laser pulse incidence angle are studied as well.

Multiple recording characteristics of polarization hologram was investigated for high density optical data storage. Polarization and angular multiplexing was performed. Some polarization holograms were independently recorded on the same position of a polarization-sensitive medium. The recorded images could be independently reconstructed.

A remarkable conversion efficiency from laser to protons is demonstrated by particle simulations in a laser-foil interaction. The total laser-proton conversion efficiency becomes 16.7% in an optimized multi-hole target, though a conventional plane foil target serves a low efficiency. When an intense short-pulse laser illuminates the thin foil target, the foil electrons are accelerated around the target by the intense laser. The hot electrons generate a strong electric field, which accelerates the foil protons, and the proton beam is generated. In our previous study, we found that multihole thin-foil target was efficient for the energy conversion from laser to protons [Phys. Rev. E 78, 046401 (2008)], and the energy conversion efficiency was 9.3%. In this paper the results clarify the role of the target hole thickness and depth in the laser-proton energy conversion. The optimized multi-hole foil target provides a remarkable increase in the laser-proton energy conversion efficiency.

Extreme ultraviolet (EUV) radiation at the wavelength of around 13nm waws observed from a laser-produced plasma using continuous water-jet. Strong dependence of the conversion efficiency (CE) on the laser focal spot size and jet diameter was observed. The EUV CE at a given laser spot size and jet diameter was further enhanced using double laser pulses, where a pre-pulse was used for initial heating of the plasma.

We propose to use an intense short pulse laser of the TEM(1,O)+TEM(O,1) mode in vacuum in order to trapand accelerate an electron bunch. The laser intensity distribution serves a confinement effect for electrons inthe transverse direction by a transverse ponderomotive force. The electrons are accelerated longitudinally bya longitudinal ponderomotive force. In our computations, we employ a three-dimensional laser field and the relativistic equation of motion including a relativistic radiation damping effect. The maximum electron energy isabout 195 [MeV} with an acceleration gradient of 5.25 [GeV/mJ at the laser intensity of 1.23x 1018 [W/cml. Anemittance of the electron bunch accelerated is small and the spatial size in the radial and longitudinal directionsare about 1000 [,um] and 10 [pm], respectively. Such the electron bunch may have potentials for nano-technologyapplications, cancer treatment, a new point light source and so on.keywords: laser acceleration, electron trapping, electron beam, ponderomotive force