%0 Journal Article %T Growth, structure and upconversion mechanisms of Ba2ErCl7 crystal %A Jianru Han %A Guangyong Zhou %A Shujun Zhang %A Zhenxiang Cheng %A Huanchu Chen %J Chinese Science Bulletin %@ 1861-9541 %D 2000 %I %R 10.1007/BF02884974 %X The methods to grow a novel upconversion crystal Ba2ErCl7 are reported in this note. Ba2ErCl7 material was synthesized with Er2O3, BaCl2ˇ¤2H2O and NH4Cl by using a so-called ˇ°direct synthesis methodˇ±. High quality Ba2ErCl7 single crystals with size up to 4 mmˇÁ8 mmˇÁ15 mm were grown by using the Czochralski and the Bridgman methods. Intense yellow-green luminescence was detected when the crystal was pumped by an 803 laser diode (LD). Transmittance spectrum was measured by using HITACH U-3500 spectrophotometer at room temperature for the first time, in which one can see that the transmittance is high in the range from 350 to 1 600 nm and the cut-off wavelength of the crystal was 230 nm. The upconversion mechanisms were discussed. %K Ba2ErCl7 %K single crystal growth %K transmittance spectra %K upconversion mechanisms %U http://link.springer.com/article/10.1007/BF02884974