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The guiding of laser ablation plasmas with axial magnetic fields has been used for many applications, since its effectiveness has been proven empirically [L. Gray et al., J. Appl. Phys. 53(10), 6628 (1982); J. Wolowski, Laser Part. Beams 20(01), 113 (2002); M. Okamura et al., Rev. Sci. Instrum. 81, 02A510 (2010); Y. Tsui et al., Appl. Phys. Lett. 70(15), 1953 (1997); C. Pagano and J. Lunney, J. Phys. D: Appl. Phys. 43(30), 305202 (2010)]. For more sophisticated and complicated manipulations of the plasma flow, the behavior of the magnetic field during the interaction and the induced diamagnetic current in the plasma plume needs to be clearly understood. To achieve the first milestone for establishing magnetic plasma manipulation, we measured the spatial and temporal fluctuations of the magnetic field caused by the diamagnetic current. We showed that the small fluctuations of the magnetic field can be detected by using a simple magnetic probe. We observed that the field penetrates to the core of the plasma plume. The diamagnetic current estimated from the magnetic field had temporal and spatial distributions which were confirmed to be correlated with the transformation of the plasma plume. Our results show that the measurement by the magnetic probe is an effective method to observe the temporal and spatial distributions of the magnetic field and diamagnetic current. The systematic measurement of the magnetic field variations is a valuable method to establish the magnetic field manipulation of the laser ablation plasma. [ABSTRACT FROM AUTHOR]

Charge state and energy distributions of ions generated by a 3 J/30 ns Nd-glass laser were measured at a distance of 3.7 m from the target for seven different elements of the Periodic Table and for two different laser power densities (of the order of 1011 and 1012 W/cm2). Two groups of elements were found: highly charged ions with ionization potentials in the range of 500–1000 eV were registered for all elements between 12C and 56Fe; at the same time, ions with about-one-order-less ionization potentials were registered for elements between 74Ge and 181Ta. The most probable reason for such a big difference is the recombination losses of ions during laser-produced plasma expansion into vacuum. Verification of recombination losses in the case of 181Ta target has shown no losses at distances longer than 32.5 cm from the target, so recombination processes should take place at shorter distances. Current densities, pulse durations, energy ranges, and numbers of ions with different charge states were found for all elements by normalizing charge state distributions to total ion currents. Two different ion groups exist for all elements and laser power densities used in experiments: the faster group has a very weak dependence of energy on ion charge state, and the energies of the slower group are proportional to the charge states with high accuracy. [ABSTRACT FROM AUTHOR]

An analysis of the specific heat behavior of pseudobinary compounds of type Er(x)Dy(1-x)Sb between 2 and 40 K, fabricated by arc-melting method, indicates a linear relationship between Dy3+ concentration and ordering temperature. A magnetic phase transition occurs in these compounds and the corresponding entropy change is almost R 1n 2. The compounds with a low concentration of Dy3+ exhibit enhanced specific heat.

Presents a study which investigated the carrier transport of electrons in inversion-mode indium phosphide metal-insulator-semiconductor field-effect transistors (MISFET). Fabrication of the corbino-disc-type MISFET; Direct current characteristics and drain-source conductance; Dependence of mobility on induced electron density and temperature.

Presents a study which investigated the effects of substrate temperature during film deposition on semi-insulating indium phosphide (InP) metal-insulator-semiconductor field-effect transistor (MISFET) characteristics. Application of MISFET; Description of the InP MISFET fabrication method; Relationship between the substrate temperature during film deposition and the behavior of effective mobility in the low temperature region.

Presents a study that evaluated the crystal structures and light absorption spectra of 1,4-dithioketo-3,6-diphenyl-pyrrolo-[3,4-c]-pyrrole (DTPP) thin films. Forms of crystal structures; Methods for the preparation of the DTPP powder; Types of crystals produced by sublimation.