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Ce:Lu 3 Al 5 O 12 single crystals grown in pure N 2 atmosphere by Czochralski method were annealed in oxidizing atmosphere (air) and reducing atmosphere (H 2 + N 2 ), respectively. Effects of annealing treatments on luminescence and scintillation properties of the crystals were investigated. The crystal annealed in air showed the highest luminescence intensity under blue light or vacuum ultraviolet excitation in comparison with that annealed in reducing flux or the as-grown crystal. Under X-ray excitation, crystal annealed in reducing atmosphere had the lowest light yield, and crystal annealed in air had the fastest decay time under 137 Cs 662 keV γ-ray excitation. Different annealing treatments resulted in different luminescence and scintillation properties, which might related with oxygen vacancies or defect existing in the crystals.

A successful direct, etching system excited by a vacuum ultraviolet hollow-cathode lamp is reported. The result shows that the facility can transfer a mesh pattern exactly and directly to n-type GaAs wafer, which is the same as that direct, etched by synchrotron radiation.

The vacuum ultraviolet (VUV) spectra of breast sickness tissues, benign or malign breast tumors were studied under the excitation of different VUV photons from a synchrotron radiation light source. The excitation spectra of different samples were monitored at 400 nm and 550 nm. The efficient excitation wavelengths were 133 nm, 193 nm and 252 nm, respectively. The differences of their fluorescence spectra were analyzed, and the results showed that their VUV spectra were different for various breast sickness tissues. There were two peaks in the spectrum when these tissues were excited by 133 nm. When 193 nm light was used to excite the tissues, there appeared a three-peak structure. There was only one distinct peak when these tissues were excited by 252 nm light. The differences of VUV spectra reflect the characteristics of various kinds of breast sickness tissues. The VUV fluorescence technique may be used in the diagnoses of breast tumor, especially available in finding the early cancers.

The properity of amorphous SiO 2 is sensitive to the irradiation of energetic ions, electron beam, X- and γ-rays, even to VUV radiation. The luminescence of a-SiO 2 and irradiated a-SiO 2 has been investigated. Here, we report that the visible light can be emitted under the excitation of Ar + ion laser from the surface of bulk fused quartz which was irradiated by “white” SR in UHV at room temperature. The emission spectrum is an asymmetry band peaked at about 625 nm, with a FWHM of about 20 nm. The SR for irradiation is from the 800 MeV storage ring without any optical elements between the light source and the samples. The vacuum is kept below 5 × 10 −7 Pa, the average beam current is 100mA and the irradiation time is 3 hours. The intensity of the luminescence is rapidly decreased under the excitation of laser. It can stand for half an hour when the power of excited laser light is kept at 2W/cm 2 approximately.

The photoluminescence of ZnO films deposited on Si substrates by reactive dc sputtering has been studied by using a synchrotron radiation (SR) light source. The excitation spectra show a strong excitation band around 195 nm related to the 390 nm emission band. Under SR vacuum ultraviolet excitation, a new emission band peaked at 290 nm was found for the first time, besides the ultraviolet emission band (390 nm) and green band (520 nm).

Pulsed laser deposition (PLD) method was used to fabricate Ni1-xFexO (x=0.02，0.05) dilute magnetic semiconductor thin films with room temperature ferromagnetism. For the Ni0.98Fe0.03O sample with a lower Fe content，the crystalline structures of the Ni1-xFexO films are of the NaCl type as determined by X-ray diffraction. For the Ni0.95Fe0.05O sample with a higher Fe content，some additional weak diffraction peaks corresponding to α-Fe2O3 phase can be observed. From the X-ray absorption near edge structure (XANES) and X-ray photoelectron spectroscopy (XPS)， it is shown that the doped Fe impurities in Ni0.98Fe0.02O are substitutionally incorporated into the NiO host and no secondary phases with room temperature ferromagnetism are found. These results show the intrinsic ferromagnetism of the Ni1-xFexO samples.

Yttrium aluminum garnet (YAG): Pr3+ is synthesized by codeposition me thod. Vacuum ultraviolet (VUV) excitation and emission spectra of YAG: Pr3+ at different temperatures are measured using synchrotron radiation as an excitation source. We analyze the transition process after excitation to 4f5d en ergy band and estimate the Huang-Rhys factor S and phonon energy ηω of YAG: Pr 3+ by multi-phonon relaxation. Emission of self-trapped exciton (STE) and 3P0→3H4,5,6 emission transferr ed from the STE energy appear when YAG: Pr3+is excited by 170nm, whic h is a different transition process from those excited by 240nm and 289nm.