Investigation of single crystal silicates for blue tunable lasers

The single crystal growth of rare earth silicates was investigated for the purpose of tunable laser hosts. Silicates of the type R2Si05, where R = La, Gd, Y, were prepared from stoichiometric melts and doped with Ce3+ activators. Seed crystals were obtained from crystallized melt sections or by growth on an iridium wire. Cathodoluminescence experiments on both powders and single crystals showed wavelength shifts with different rare earth ions. The Gd, Y, and mixed crystals of Gd-Y silicates gave good bright emission with Ce3+. The emission is broad band and covers the wavelength range of 370 to 525 micron. The peak emission can be centered near 450 to 460 micron by other compositions. Larger single crystals for laser hosts are under development.