The third-order nonlinear optical susceptibility, (3) , of lanthanide (lanthanum, praseodymium, neodymium, and samarium) borate glasses has been measured by the third harmonic generation method. The structure of the present glass system has been studied by infrared and Raman spectroscopic methods. The network structures of the present Ln 2 O 3 -B 2 O 3 glasses have been confirmed to be basically similar to each other. Praseodymium, neodymium, and samarium borate glasses exhibit (3) values that are larger than lanthanum borate glasses, because of the optical resonance effect, in accordance with the f-f transition. Especially, the (3) value for 30Pr 2 O 3 ⅐70B 2 O 3 glass is 1.8 × 10 −12 esu, which is a factor of ∼60 larger than that of SiO 2 glass. This striking enhancement of (3) is mainly attributed to the large transition moment to the first excitation state.

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We synthesized Pd-Fe series nanoparticles in solid solution using pulsed plasma in liquid with Pd-Fe bulk mixture electrodes. The Pd-Fe atomic percent ratios were 1:3, 1:1, and 3:1, and the particle size was measured to be less than 10 nm by high-resolution transmission electron microscopy (HR-TEM). The nanoparticles showed face-centered cubic structure. The lattice parameter increased with increasing Pd content and followed Vegard’s law, and energy-dispersive X-ray spectra were consistent with the ratios of the starting samples, which showed a solid solution state. The solid solution structure and local structure were confirmed by HR-TEM and X-ray absorption fine structure.

FePt alloys are an important class of materials in permanent magnetic applications because of their large uniaxial magnetocrystalline anisotropy and good chemical stability. We have applied the pulsed plasma in liquid method to synthesis nanoparticles. Short duration of pulse and quenching effects of the surrounding liquid limit the size of crystal. That enable synthesis of small size and metastable nanoparticles. In this study, ferromagnetic FePt nanoparticles were successfully synthesized. Face-centered-cubic (FCC) A1-type phase was synthesized from FePt (Fe:PT=50:50, 55:45 in atomic %) alloy rod electrodes using the pulsed plasma in ethanol. The ordered face-centered-tetragonal (FCT) L10-type phase FePt was obtained by annealing the A1-type phase at 400oC for 1 h. The average diameter of L10-type FePt nanoparticles was less than 10 nm. Vibrating Sample Magnetometer (VSM) analysis showed that the coercivity of L10-type nanoparticles was much larger than that of the A1-type phase nanoparticles.