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Anomalous observations using the fast ignition for laser driven fusion energy are interpreted and experimental and theoretical results are reported which are in contrast to the very numerous effects usually observed at petawatt-picosecond laser interaction with plasmas. These anomalous mechanisms result in rather thin blocks (pistons) of these nonlinear (ponderomotive) force driven highly directed plasmas of modest temperatures. The blocks consist in space charge neutral plasmas with ion current densities above 1010A∕cm2. For the needs of applications in laser driven fusion energy, much thicker blocks are required. This may be reached by a spherical configuration where a conical propagation may lead to thick blocks for interaction with targets. First results are reported in view of applications for the proton fast igniter and other laser-fusion energy schemes.

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In recent years, with increasing developments in the electronics industry, electronic components have been required with smaller size, higher performance, and multifunction capability. Therefore, composites, especially ferromagnetic-ferroelectric composites, have been attracting more and more attention. [1][2][3] When a ferromagnetic and ferroelectric phase coexist in one material, novel properties, such as magnetoelectric and magneto-optic properties, are expected due to the interaction between magnetization and electric polarization. [1,4] Therefore, much work on ferromagnetic-ferroelectric composites has been carried out. [1][2][3][4][5] However, many reports, including the authors' previous work, [3] indicate that the introduction of low-dielectric-constant (e) ferrite and the defect reaction between the ferrite and ferroelectric phases would result in a low dielectric constant for the composite, which is not compatible with the trend for higher capacitance and smaller size for electronic components. On the other hand, according to percolation theory, the dielectric constant depends strongly on the conductivity ratio of the ferroelectric and ferrite phases: [6][7][8] ). Thus, properties such as high permeability and a high dielectric constant are expected for this ferrite-ferroelectric composite. In this Communication, the magnetic and dielectric properties of the composite were investigated, and a considerable permeability and an unusually high dielectric constant were observed. In other words, we fabricated a composite system combining the merits of both the ferromagnetic-ferroelectric properties and percolative effect. We consider that this experiment could provide a new manufacturing method for ferromagnetic-ferroelectric composites with ultrahigh capacitance.The X-ray diffraction (XRD) patterns are shown in Figure 1. It can be seen that NZFO and BT phases coexisted in the composite. The NZFO had a typical spinel structure and the BT had a tetragonal perovskite structure in all the composites. All of the peaks can be identified and no intermediate phase was observed by using XRD, which indicates that no significant chemical interaction occurred between the BT and NZFO phases.The dielectric and magnetic properties of the ferroelectricferromagnetic composites depended strongly on their microstructure. Therefore, three typical microscopy images of the samples are shown in Figure 2. In the biphase-structured composites, the grain size of the NZFO phase (about 0.8 lm) was much smaller than that in an NZFO single-phase-structured ceramic (about 5 lm). From these observations, it seems that the perovskite phase inhibits the grain growth of NZFO in the composite system. Furthermore, compared to the compact structure of the plain NZFO ceramic (i.e., NZFO volume fraction, f NZFO = 1), large pores appear in the composite with