No abstract

Cathodoluminescent properties of Eu2+‐ or Ce3+‐activated normalMgS and Ca1−xMgxS phosphors are investigated at 300 K. It is found that normalMgS:normalEufalse(0.01 normalmole percent false[normalm/normalofalse]false) exhibits a high energy efficiency (∼16 %) and an improved water‐resistance if residual oxide content is less than 1 m/o. Under these highly sulfurizing conditions, normalMgS is confirmed to be completely miscible with normalCaS in any compositional ratio. The composition Ca0.1Mg0.9S:normalEufalse(0.05 normalm/normalofalse) , Ba(0.1 m/o), whose color coordinates are comparable to the red phosphor false(Y0.964Eu0.036)2O2S , exceeds the latter in brightness by 15% at 18 kV excitation. Additionally, Eu2+‐activated alkaline‐earth binary sulfides are examined. A complete miscibility is ascertained in the pseudobinary system where the difference in cation radius is less than 0.035 nm. Stress‐induced peak shifts are observed in normalMgS:normalEu and A1−yBySfalse(AnormalorB≡normalMg,normalCa,normalSr or Ba,A≢Bfalse) . Some mechanisms for these shifts are proposed.

High optical sensitivity is observed in 0.1 wt% Ce-doped strontium barium niobate (SBN) crystals in the absence of an external electric field. Only 5–10 mJ/cm2 of incident 0.488-μm radiation is required to produce 10% diffraction efficiency, while the energy to erase holograms from the 80% to its 1/e diffraction efficiency level is 30–40 mJ/cm2 at the same wavelength. Holograms stored in Ce-doped SBN persist at least one month (decay time constant) if kept in the dark at room temperature.

No abstract

MgS:Eu (0.01 mol‐%) zeigt eine hohe Energieausb.