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Monocrystalline SiC, Si and Diamond detectors have been used to monitor the radiations emitted from TNSA laser-generated plasma using a high-intensity fs laser. The comparison of their spectra was performed monitoring in time-of-flight the forward emitted TNSA plasma radiation. Carbon, aluminum, copper and gold targets were irradiated with an intensity of the order of 1019 W/cm2. SiC detector, with 80 microns depth active region, gave the best response to detect fast UV and X-rays, relativistic and cold electrons, and energetic protons and light accelerated ions. The experiments demonstrate the advantages to use semiconductor detectors to characterize the plasma enhancing the importance of the thickness of the target with respect to its electronic density.

A ns Nd:YAG pulsed laser has been employed to produce plasma from the interaction with a dense target, generating continuum and UV and soft x-ray emission depending on the laser parameters and target properties. The laser hits solid and gaseous targets producing plasma in high vacuum, which was investigated by employing a silicon carbide detector. The two different interaction mechanisms were studied, as well as their dependence on the atomic number. The photon emission from laser-generated plasma produced by solid targets, such as boron nitride (BN) and other elements (Al, Cu, Sn and Ta) and compounds such as polyethylene, has been compared with that coming from plasma produced by irradiating different gas-puff targets based on N2 and other gases (Ar, Xe, Kr, SF6). The experimental results demonstrated that the yields are comparable and, in both cases, increase proportionally to the target atomic number. The obtained results, focusing the attention on the advantages and drawbacks of the employed targets, are presented and discussed.

Target normal sheath ion acceleration is applied with a high contrast fs laser irradiating advanced targets based on thin metallic films (Al, Cu, Ag and Au) covering micrometric foils of reduced graphene oxide (rGO). The laser intensity is of about 1018 W/cm2 and the laser focal position with respect to the target surface is optimized to have the maximum proton acceleration. Plasma diagnostics are investigated using time-of-flight technique employing SiC detectors, ion collectors, and gaf-chromic films. Micrometric aluminum absorbers were employed to separate the faster proton detection by other accelerated ions. At the optimized laser focal position, the maximum proton acceleration of 2.5 MeV and 3.0 MeV energy was obtained using Ag(200 nm) and Au(200 nm) covering rGO(7 μm) targets, respectively. The high proton energy is due to the high electrical and thermal conductivity and high mechanical resistance of the used rGO foils and to the high plasma electron density of the target.

Graphene oxide foils implanted with copper ions at low energy and high dose, have been proposed as hybrid graphene-based materials suitable to be laser irradiated in vacuum to produce hot plasmas. The special lattice structure of the graphene oxide foil can improve the propagation of the laser accelerated electrons inside the foil and to enhance the electron density emerging from the rear foil surface. In such conditions the electric field developed in the non-equilibrium plasma increases and consequently in the forward ion acceleration. The foils have been optimized in thickness and they were irradiated with optimized laser parameters in order to produce high energy and quasi-monoenergetic proton beams by the femtosecond laser at the Institute of Plasma Physics and Laser Microfusion in Warsaw, Poland. Gaf chromic film and silicon carbide detectors were used to monitor the plasma properties and to measure the velocity of the emitted protons and carbon ions from plasma.

The development and demonstration of a table-top transmission soft X-ray (SXR) microscope, using a laboratory incoherent capillary discharge source has been carried out. This Z-pinching capillary discharge water-window SXR source, is a first of its kind to be used for high spatial resolution microscopy at λ = 2.88 nm (430 eV) . A grazing incidence ellipsoidal condenser mirror is used for focusing of the SXR radiation at the sample plane. The Fresnel zone plate objective lens is used for imaging of the sample onto a back-illuminated (BI) CCD camera. The achieved half-pitch spatial resolution of the microscope approaches 100 nm, as demonstrated by the knife-edge test. Details about the source, and the construction of the microscope are presented and discussed. Additionally, the SXR images of various samples, proving applicability of such microscope for observation of objects in the nanoscale, are shown.

Microscopes operating at short wavelengths, in the extreme ultraviolet and soft x-ray spectral region, require careful condenser positioning to avoid possible artifacts related to enhancing or diminishing certain spatial frequencies in the image plane. Various methods are often used to visualize the condenser illumination pattern, including direct visualization on a CCD camera; however, these are not always straightforward to use. We present and discuss a novel and convenient method to image a condenser illumination pattern upstream the sample plane, using two zone plates with matched numerical apertures. This imaging system, operating herein in the water-window spectral range in telescope configuration, allows us to change the distance between the conjugated planes, thus overcoming limitations related to the geometry of the vacuum system. This geometry, which is optimized for the highest possible spatial resolution allowed by the zone-plate objective, is not necessarily particularly good for visualization of the condenser illumination pattern. The presented method was demonstrated with a compact, gas puff target source based soft x-ray microscope, which is capable of resolving 60 nm features (half-pitch resolution), requires a few seconds exposure time, and is debris-free due to the gaseous nature of the target for soft x-ray generation. The method, presented herein, may solve mentioned vacuum system geometry limitations. Also, it can easily be extended to other systems and other wavelengths, provided a proper optic is used. Modes of operation and the results are presented and discussed.