Articles you may be interested inLuminescence properties and scintillation response in Ce3+-doped Y2Gd1Al5-xGaxO12 (x = 2, 3, 4) single crystals J. Appl. Phys. 116, 083505 (2014); 10.1063/1.4893675Yttrium antisite reduction and improved photodiode performance in Ce doped Y3Al5O12 by Czochralski growth in alumina rich melts Czochralski growth of cerium-doped Lu 1.8 Y 0.2 SiO 5 ͑LYSO͒ from a 90/10 solution of Lu 2 SiO 5 ͑LSO͒ and Y 2 SiO 5 ͑YSO͒ is demonstrated. The alloyed scintillator retains the favorable growth properties of YSO and the desirable physical and optical scintillator properties of LSO. Radioluminescence, thermally stimulated luminescence, optical absorption, and lifetime measurements confirm the equivalence of LYSO and LSO optical properties. Advantages of LYSO Czochralski growth relative to LSO include reduced melting point, less propensity for formation of crystalline inclusions, lower cost of starting material, and easier incorporation of cerium into the host lattice. This material offers an attractive alternative to LSO for scintillator applications.

We have experimentally demonstrated infrared second-harmonic generation in the nonbirefringent zincblende crystal cadmium telluride using properly oriented plates in which the optical path length is equal to an odd number of coherence lengths. The present process has the promise of scalability to high power, since suitable zinc-blende cubic crystals can be grown in large boules of excellent optical quality.

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A short actively mode-locked XeCl oscillator has produced 120-ps duration pulses for the first time. The pulses have an energy of 15 μJ and a modulation depth of >95%. The evolution of the pulsewidth during the mode-locked pulse train was also measured.

Thin films of (Y 0.92 Eu 0.08 ) 2 O 3 were synthesized through chemical vapor deposition of b-diketonate precursors onto glass and sapphire substrates. The films were weakly luminescent in the as-deposited condition and were composed of spherical particles 3 mm in diameter. A KrF laser was pulsed for 25 ns from 1-3 times on the surface of the films. One pulse was sufficient to melt the film and repeated pulses caused ablation of the material. Melting of the film smoothed the surface, increased the density, and increased the photoluminescent emission intensity.When a high intensity ultraviolet (UV), pulsed photon beam is absorbed by the surface of a material, the transfer of energy produces a high local temperature. This can be used to melt and subsequently solidify the irradiated area and/or to simply alter the surface structure of the solid. The transfer of UV laser energy into the surface of a solid is the basis a nonconventional processing technique called pulsed laser melting that has been developed for rapid melting and subsequent crystallization of semiconductors. Pulsed excimer lasers have been used to crystallize amorphous lead titanate films 1 and amorphous semiconductors 2-5 induce grain growth in silicon through melting and solidification, 6 and to clean and smooth the surfaces of materials. 7 Phosphors are inorganic solids that emit light when excited with an external energy source such as high energy photons, electrons, or an electric field. Europium doped yttrium oxide [Y 2 O 3 : Eu 31 or (Y 12x Eu x ) 2 O 3 , x < 0.10] is a well-known photo-and cathodoluminescent phosphor used in the lighting industry and in cathode ray tube displays. The material luminesces a red/orange color (peak wavelength 611 nm) when excited by high energy photons or electrons. The luminescence arises from the 4f ! 4f electronic transitions of the Eu 31 ion.For flat panel display applications, thinner phosphor screens are required in order to increase light transmission (to the viewer), improve spatial resolution, reduce saturation effects, and reduce the cost. However, low temperature thin-film deposition techniques (e.g., sputtering, evaporation, chemical vapor deposition, laser ablation, etc.) typically produce amorphous or poorly crystalline films that require high temperature annealing to optimize the luminous efficiency. It is well documented that an increase in processing or postsynthesis annealing temperature increases the luminescent efficiency of Y 2 O 3 : Eu 31 . 8 Unfortunately, these temperatures are higher than the use temperature of low-cost glass (e.g., Corning 7059 which has a strain point of 2600 ± C), a desirable substrate from a manufacturing point of view. This is a major stumbling point in utilizing thin-film phospors.Thermal processing by laser treatment has many advantages over standard heat treatment methods. For example, the substrate is not exposed to elevated temperatures that can cause chemical reactions between the substrate and film or cause degradation of the substrate. Additionally, the proces...