YbxY1-xAl3(BO3)4(x=0.1,0.07 and 0)crystals have been grown by the flux method.The growth defects of YbxY1-xAl3(BO3)4 crystals were detected by X-ray topography.It is found that the perfcetion of YbYAB crystal with low...YbxY1-xAl3(BO3)4(x=0.1,0.07 and 0)crystals have been grown by the flux method.The growth defects of YbxY1-xAl3(BO3)4 crystals were detected by X-ray topography.It is found that the perfcetion of YbYAB crystal with low Yb dopant is better than that with high Yb dopant.In Yb0.1Y0.9Al3(BO3)4 crystal,growht bands,growth boundaries,grown-in dislocations and inclusions were observed.Howver,the densities of growth defects for Yb0.07Y0.93Al3(BO3)4 and YAl3(BO3)4 are low and no obvious inclusions are observed in these crytals.In addition,growth twins wrer detected in YbxY1-xAl3(BO3)4 crystal by using the chemical etching method.It is found that the growth twins occur frequently in Yb0.01Y0.9Al3(BO3)4 crystal whereas no growth twin appears in YAl3(BO3)4 crystal. Based on the experimental observations,the formation mechanism of growth twins is discussed.In the meantime,the effective measures for reducing the growth twins and defects are proposed.2001 Elsevier Science B.V.All rights reserved.展开更多
Growth and morphology of neodymium or ytterbium doped calcium gadolinium yttrium oxoborate (Re∶Ca 4Gd x Y 1- x O(BO 3) 3(Re∶GdYCOB)Re =Nd,Yb; x =0-1)were systematically studied. Polycrystalline materials used for Re...Growth and morphology of neodymium or ytterbium doped calcium gadolinium yttrium oxoborate (Re∶Ca 4Gd x Y 1- x O(BO 3) 3(Re∶GdYCOB)Re =Nd,Yb; x =0-1)were systematically studied. Polycrystalline materials used for Re∶GdYCOB single crystals growth were synthesized by multistage solid phase reaction method.Re∶GdYCOB single crystals were grown by Czochralski technique.The pulling rates are 0.5-2mm/h and the rotation rates are 10-30r/min.Usually 65-75% polycrystalline materials can be transformed into good quality single crystals under our growth conditions. The structures of some as grown Re∶GdYCOB single crystals were measured by using a four circle diffractometer.The results measured show that the space group of the crystals is C 3 s Cm.The determined lattice constants of 8 at% Nd doped Ca 4YO(BO 3) 3 single crystal are a =0.8076nm, b =1.6020nm, c =0.3527nm , β =101.23°.展开更多
文摘YbxY1-xAl3(BO3)4(x=0.1,0.07 and 0)crystals have been grown by the flux method.The growth defects of YbxY1-xAl3(BO3)4 crystals were detected by X-ray topography.It is found that the perfcetion of YbYAB crystal with low Yb dopant is better than that with high Yb dopant.In Yb0.1Y0.9Al3(BO3)4 crystal,growht bands,growth boundaries,grown-in dislocations and inclusions were observed.Howver,the densities of growth defects for Yb0.07Y0.93Al3(BO3)4 and YAl3(BO3)4 are low and no obvious inclusions are observed in these crytals.In addition,growth twins wrer detected in YbxY1-xAl3(BO3)4 crystal by using the chemical etching method.It is found that the growth twins occur frequently in Yb0.01Y0.9Al3(BO3)4 crystal whereas no growth twin appears in YAl3(BO3)4 crystal. Based on the experimental observations,the formation mechanism of growth twins is discussed.In the meantime,the effective measures for reducing the growth twins and defects are proposed.2001 Elsevier Science B.V.All rights reserved.
文摘Growth and morphology of neodymium or ytterbium doped calcium gadolinium yttrium oxoborate (Re∶Ca 4Gd x Y 1- x O(BO 3) 3(Re∶GdYCOB)Re =Nd,Yb; x =0-1)were systematically studied. Polycrystalline materials used for Re∶GdYCOB single crystals growth were synthesized by multistage solid phase reaction method.Re∶GdYCOB single crystals were grown by Czochralski technique.The pulling rates are 0.5-2mm/h and the rotation rates are 10-30r/min.Usually 65-75% polycrystalline materials can be transformed into good quality single crystals under our growth conditions. The structures of some as grown Re∶GdYCOB single crystals were measured by using a four circle diffractometer.The results measured show that the space group of the crystals is C 3 s Cm.The determined lattice constants of 8 at% Nd doped Ca 4YO(BO 3) 3 single crystal are a =0.8076nm, b =1.6020nm, c =0.3527nm , β =101.23°.