报告题目：介电无机材料晶体、熔体及玻璃超高温拉曼光谱研究
     High temperature Raman spectroscopy of crystalline, molten and vitreous states of dielectric inorganic materials at ultrahigh temperatures
报告内容简介：High Temperature Raman Spectroscopy (HTRS) is the informative method for studying “in situ“ phase transformations and a behavior of the structure of oxides materials at a high temperature. These materials are used widely as laser media, optic fibers and as micro- and nano-materials. The synthesis from the melt is the main technique for the production of oxide single crystals. The information on the formation of a molten state and on a behavior of the oxide materials structure in the growth processes is necessary for a modification of synthesis conditions. It is this information that can be received with HTRS technique. It was difficult to use HTRS for investigation of oxide compounds with high melting point due to a high thermal radiation of the furnace and the sample, which interfered with a registration of a week signal of Raman scattering. HTRS technique, developed by us in 1980, permitted to increase the temperature of experiments up to 2200K and to study the materials in crystalline, molten and vitreous states in a polarized light. In contrast to the conventional Raman spectroscopy technique we used a copper vapor laser as an excitation source, operated in a pulse repetition regime with a frequency of 15 kHz and the pulse power duration of 10- nsec. An average power was 10 W and a peak pulse power was about 30-50 kW. High laser peak pulse power resulted in a large contrast between the Raman scattering signal and the thermal radiation background. There was signal gating circuit with the duration time of 11 nsec. A thermal irradiation background was suppressed in 104 times.
报告人姓名：Sobol A.A.      俄科学院普洛克霍夫普通物理研究所
报告人简介：亚历山大索伯博士出生于1941年，1967年毕业于莫斯科动力工程学院。先在俄罗斯科学院列别捷夫物理研究所从事科学研究，1976年获得博士学位。自1983年，在俄科学院普洛克霍夫普通物理研究所从事科学研究，并为实验室的负责人，迄今发表或获得了120篇的科学论文和专利。国际上首次创建高温拉曼光谱技术。代表作：1. Journal of Molecular Structure, 2011, 1008: 69-76 2. Inorganic Materials, 2012, 48(7): 732-737
报告时间：2013-10-17 14:00
报告地点：线上赌博安卓版延长校区日新楼401室