Stimulated Raman scattering(SRS) used for shifting the frequency of laser radiation to new spectral regions where direct laser oscillation is not available or ineffective, has attracted much attention for their wide applications in medicine, ultra-fast laser spectroscopy, ecological monitoring techniques, laser guide stars and up-conversion fiber lasers. As one of the earliest third-order nonlinear optical process, SRS was discovered by Woodbury and Ng. Since then, intensive investigation were made on SRS and a large number of crystals were reported as promising candidates for efficient Raman shifting, including some tungstates (BaWO₄, KGd(WO₄)₂, SrWO₄, PbWO₄), nitrates(Ba(NO₃)₂) and vanadates (YVO₄, GdVO₄). As one kind of perspective Raman materials, however, there have no reports about the SRS with Ba₂TiSi₂O₈ crystal.

    The purpose of our experimental study was to examine the steady state Raman gain and the thresholds for the onset of SRS of BTS crystal with picosecond pumping. Stimulated Raman scattering of 30ps laser at 532 nm pulses were investigated in single-pass scattering arrangement. The first and second Stokes Raman gain coefficients were measured to be 5.08 cm/GW and 3.53 cm/GW at 532 nm, respectively. The highest first Stokes conversion efficient in a single-pass arrangement was 31.8%. Meanwhile, we measured the thermal properties of Ba2TiSi2O8, including the measured specific heat, thermal expansion, thermal diffusivity coefficient and thermal conductivity for the first time. The thermal expansions at room temperature are ɑa=3.72×10-6 K-1, ɑc=11.1×10-6 K-1. The thermal diffusivity coefficient at 296K are κ11=1.83 W•m-1•K-1, κ33=0.708 W•m-1•K-1. All the results show that Ba₂TiSi₂O₈ crystal is a new Raman material for the generation of frequency shifted Raman laser pulses.

• Legal notice:
  

  Copyright (c) Pielaszek Research, all rights reserved.
  The above materials, including auxiliary resources, are subject to Publisher's copyright and the Author(s) intellectual rights. Without limiting Author(s) rights under respective Copyright Transfer Agreement, no part of the above documents may be reproduced without the express written permission of Pielaszek Research, the Publisher. Express permission from the Author(s) is required to use the above materials for academic purposes, such as lectures or scientific presentations.
  In every case, proper references including Author(s) name(s) and URL of this webpage: https://science24.com/paper/29702 must be provided.