Study On The Growth And Properties Of Er³⁺ And Yb³⁺ Doped Ky (wo₄)₂ Laser Crystal

21st century is the photoelectron era. Many developed countries regard the development of solid-state laser device to the height of national development strategies. The rapid developments of fiber communication, laser ranging and laser medical treatment need corresponding development of 1.5μm wavelength lasers, which is eye-safe wavelength. People are more and more interested in the study of such lasers. As we all know, Er3+is used as activation ion, and can generate near 1550 nm fluorescence through the transition of 4I13/2â†'4I15/2, such as crystal material GdCa4O(BO3)3(GdCOB4), YCa4O(BO3) 3 (YCOB), YAG, YVO4, KGW and so on. But the absorption of Er3+ ion in the crystal from pump light and semiconductor laser is weak, which result in the high laser threshold of general doped Er3+ ion laser crystal. According to literature, Yb3+ ion in the crystal can be used as an effective sensitizer of Er3+ ion, and the absorption wavelength of Yb3+ ion is about 980 nm, which match with the wavelength of LD commercialization. It may improve pumping efficiency and it don't need the cooling system. So efficient, all-solid and structure-compact laser may be made. Er3+/Yb3+ double-doped laser material has become one of interests in the research.KY(WO4)2 (short for KYW)crystal is an important laser host material, which is monoclicnic system. The space group is C2/c,a=10.61 A, b=10.29 A, c=7.49 A,β=130.65°. Crystal growth is the important branch of the materals science. In this paper, double-doped Er3+/Yb3+ (the molar concentration of Er3+ and Yb3+ both are 5%) in KY (WO4)2 (Er/Yb:KYW) crystal was grown by Top Seeded Solvent Growth (TSSG). The complete monocrystal was obtained by optimizating crystal growth process parameters. In order to comparative study the spectrum property, ErKYW and Yb:KYW with the same concentration as the double-doped crystal were grown by TSSG.KYW crystal is birefringent crystal and has anisotropy. In this paper, the absorption spectra, fluorescence and up conversion spectra in main refractive index axes have been studied. The results showed that fluorescence intensity of the crystal made a great deal of difference by different direction. So the appropriate polarization direction of pumping light and crystal axes should be considered when the laser diode pumping laser is designed. The contrastive analysis between Er/Yb:KYW and Er:KYW and Yb:KYW showed that Yb3+ doped into Er:KYW as sensitizer was efficient and feasible.KYW crystal with self-raman characteristics is a potential laser crystal applied for multi-wavelenth laser. In this paper, the incidence vibration and the absorbing vibration of the Raman vibration mode in different directions were experimented, and the Raman vibration mode and anisotropy of KYW crystal were analyzed theoretically. It showed that different incident and receiving directions affected Raman spectra. The up conversion fluorescence of the double doped crystal were also studied.The up conversion green glow and red glow were got through Er3+/Yb3+:KYW crystal of 980nm LD pumping. The relative intensity of green glow was great but the red glow was low, because the concentration ratio of the crystals which was studied was 1:1. And the up conversion fluorescence in different directions were tested, the result showed that there were all clear up conversion green glow, which will provide with basic experiment data for people to look for laser medium for designing green laser.