Tbe absolute photoionization cross section for tbe excited 7p state of K has been measured using the method of ionization saturation. The measured cross sections u , ~ (321.8nm) and uTP (643.6nm) are (0.9f0.6) M b and (1.9f0.9) Mb, respectively. Tbe results are in good agreement with the calculated values.

We report the first experimental investigation of the photoionization cross-sec-tions of singlet excited ststes 3858's and 3s4d'D in atomic magnesium, which can not be directly reached from the ground state. The measured absohte values are us.5.1S (571.lnm)=(0.27fO.O9)Mb and (TJs#D (552.8nm)=(2.6fO.9)Mb. Theoretical calculations were given, which are in good agreement with the measured values.

We report the fabrication of high temperature superconducting YBaz C u 3 Orwz thin films on CaNdAlO4 (100) substrate by pulsed laser deposition. Films have excellent features. X-ray diffraction patterns show thaf thin films are epitaxial with c-axis orientation normal to the surface of substrate. The four-terminal measurements indicate the zero resistance temperature of 92.1K. and transition width of 0.7K, the critical current density of 3 x lo6 A/cmZ a t 77K and under zero magnetic field.