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Compact soft X‐ray laser has been developed. In past experiments, spike output has been observed, when operating the device with a predischarge current of 5 to 15 A, a current of 9 to 35 kA with a rise time of 55 ns in an argon gas pressure range from 100 to 800 mTorr. Spectroscopic measurement has been conducted using a grazing incidence spectrometer. The line at 46.9 nm has been observed. In present study, varying the capillary length, the X‐ray diode measurement has been conducted. The result shows that the laser output exponentially increases with increasing the capillary length. The divergence of laser beam is also measured. For the 20 cm‐long capillary, the diameter of a laser beam is in a range from 3.2 to 4.0 mm, which is corresponding to a range of divergence from 2.2 to 2.8 mrad.

The authors studied luminescence polarization of individual NN centers in GaP:N and discussed the atomic configurations. In addition to the widely known green luminescence centers, NN1∼NN10, new luminescence centers were observed in the infrared spectral region, which may be due to the true nearest‐neighbor NN pair.

A laser triggerd discharge produced Sn plasma light source has been developed. Experimental parameters such as electrode separation and laser irradiation power are varied to optimize EUV emission power. It is clear that the maximum EUV radiation was occurred in the position where the pinch was observed.

Effects of beam loading on the induction voltage modulator have been experimentally evaluated using a FET (field effect transistor) based driving pulser and a resistive secondary circuit. The core materials used in this study, are made of a nano-crystalline alloy (Finemet) and a Co-amorphous alloy. The voltage modulation is evaluated as a function of magnetization rate dB/dt, magnetization level of the magnetic material and the current rise-rate of the secondary loop (dI/dt). Experimental results indicate that the voltage modification depend not only on the magnetization rate but also on the initial state of the magetic materials and also flux swing B from it. These results indicate that the response of the modulator against the loading depends on the transient magnetic-domain motion in the core materials.

Preliminary experiments were performed to investigate the fundamental characteristics of the laser produced plasmas and the KrF lasers for the pulsed ion beam production. (1) Lithium target was irradiated by a small e‐beam pumped KrF laser and the exhausted plasmas were measured. (2) A larger KrF laser of the same kind was operated and the output characteristics were observed. (3) The mode patterns of a discharge‐pumped KrF laser was also measured most recently to prepare the future target irradiation to produce ion‐source plasmas.

Recent laser assisted works for pulsed ion beam drivers are described in this paper. The first one is a plasma production by a KrF laser light which may be applicable to an ion source. The second item is a transverse‐mode‐diagnostic of a discharge‐pumped laser. The third one is a one‐dimensional computation of the latter laser.