Pure and neodymium-doped gadolinium calcium oxoborate crystals of high quality were grown by the Czochralski method.The orientation of crystal was precisely determined,and the samples for measurements were prepared.Th...Pure and neodymium-doped gadolinium calcium oxoborate crystals of high quality were grown by the Czochralski method.The orientation of crystal was precisely determined,and the samples for measurements were prepared.Through synchrotron x-ray topography and high-resolution x-ray diffractometry,the twin structure was discovered.Some properties such as the figure of merit value,and dielectric,piezoelectric,and elastic constants were meausured along with a discussion of the anisotropy of the laser properties.展开更多
Large GdCa4O(BO3)3 crystal has been grown by the Czochralski method.The quality of GdCa4(BO3)3 crystal was assessed by white-beam synchrotron radiation topography.It has been found that there is a sub-grain boundary i...Large GdCa4O(BO3)3 crystal has been grown by the Czochralski method.The quality of GdCa4(BO3)3 crystal was assessed by white-beam synchrotron radiation topography.It has been found that there is a sub-grain boundary in the GdCa4O(BO3)3 crystal.The boundary divides the large GdCa4O(BO3)3 crystal into two individuals.Due to the misorientation between the two individuals,the image shifts can be observed in the synchrotron topopraphs.Based on the misorientation determined by high resolution X-ray diffractometer,the image shifts were calculated for several reflections.The calculations are in agreement with the measurements from the topogrphs very Well.In addition,the formation mechanism of sub-grain boundary is discussed.2001 Elsevier science B.V.All rights reserved.展开更多
文摘Pure and neodymium-doped gadolinium calcium oxoborate crystals of high quality were grown by the Czochralski method.The orientation of crystal was precisely determined,and the samples for measurements were prepared.Through synchrotron x-ray topography and high-resolution x-ray diffractometry,the twin structure was discovered.Some properties such as the figure of merit value,and dielectric,piezoelectric,and elastic constants were meausured along with a discussion of the anisotropy of the laser properties.
文摘Large GdCa4O(BO3)3 crystal has been grown by the Czochralski method.The quality of GdCa4(BO3)3 crystal was assessed by white-beam synchrotron radiation topography.It has been found that there is a sub-grain boundary in the GdCa4O(BO3)3 crystal.The boundary divides the large GdCa4O(BO3)3 crystal into two individuals.Due to the misorientation between the two individuals,the image shifts can be observed in the synchrotron topopraphs.Based on the misorientation determined by high resolution X-ray diffractometer,the image shifts were calculated for several reflections.The calculations are in agreement with the measurements from the topogrphs very Well.In addition,the formation mechanism of sub-grain boundary is discussed.2001 Elsevier science B.V.All rights reserved.