Nanocrystalline Ce 1−x RE x O 2−y ͑RE= La and Nd͒ powders were synthesized with a controlled size in the range of 3-5 nm using microemulsion technique. The nanoceria retains its cubic fluorite structures for the complete doping range. X-ray diffraction and Raman spectroscopic studies showed that the lattice distortion increased with the doping amount and was found to be higher for La-doped samples compared to the Nd doping. Spatial correlation model used for Raman analysis suggested increased defect concentration for the doped samples compared to nanoceria.

An experimental system has been assembled to measure the absolute values of the Raman gain spectrum for millimeter-thick glass samples. Results are reported for two new oxide glasses with Raman gain coefficients as much as 30 times larger than that of fused silica and more than twice its spectral coverage.

Recent STAR measurements suggest a difference in the global spin polarization between hyperons and anti-hyperons, especially at relatively low collision beam energy. One possible cause of this difference is the potential presence of in-medium magnetic field. In this study, we investigate the phenomenological viability of this interpretation. Using the AMPT model framework, we quantify the influence of different magnetic field evolution scenarios on the size of the polarization difference in a wide span of collision beam energies. We find that such difference is very sensitive to the lifetime of the magnetic field. For the same lifetime, the computed polarization difference only mildly depends on the detailed form of its evolution. Assuming magnetic polarization as the mechanism to enhance anti-hyperon signal while suppress hyperon signal, we phenomenologically extract an upper limit on the needed magnetic field lifetime in order to account for the experimental data. The so-obtained lifetime values are in a quite plausible ballpark and follow approximately the scaling relation of being inversely proportional to the beam energy. Possible implications on other magnetic field related effects are also discussed.

Several different compositions of tellurium-thallium oxide glasses were fabricated and tested for their Raman gain performance. The addition of PbO to the glass matrix increased the surface optical damage threshold by 60-230%. The maximum material Raman gain coefficient experimentally obtained was (58 +/- 3) times higher than the peak Raman gain of a 3.18 mm thick Corning 7980-2F fused silica sample (Deltanu = 13.2 THz). The highest peak in the Raman gain spectrum of the tellurium-thallium glass is attributed to the presence of TeO3 and TeO3+1 structural units with thallium ions in the vicinity at a frequency shift near 21.3 THz.

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