Search and development of nonlinear optical glasses with a high FOM

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A purpose of the present study was to search and develop novel nonlinear optical materials based on the simultaneous measurements of signs, and real and imaginary parts of the third order nonlinear optical susceptibility χィイD1(3)ィエD1 by using the Z-scan measurement system newly purchased. Crystalline and amorphous oxide materials containing organic dyes, heavy metal ions, or transition metal ions are considered to be promising candidates for novel third order optical nonlinear materials with a high FOM.Although we have tried to measure the third order nonlinear optical susceptibility χィイD1(3)ィエD1 by using a ps-YAG laser as an excitation source, instability of the ps-YAG laser was a serious problem to the acquisition of reliable data. Therefore, many efforts were made to achieve last instability. As a result, this problem has now been solved especially by the strict temperature control of a room and by an improvement of laser cooling systems. It takes, however, much time to analyze fact … More ors causing the instability . Open and closed aperture scans are usually carried out independently for conventional Z-scan measurement system. This takes much time to obtain a spectrum, so that the fluctuation of laser emission greatly affects the accuracy of the experimental result. Here, additional improvements have been made for our Z-scan measurement system. First, optics have been arranged so as to measure the open and closed aperture spectra at the same time. Second, electronics have also been modified to synchronize data collection with laser emission by a computer. These modifications successfully lead to a reduction of measuring time to a half and an increase of data accuracy over the system currently in use. In fact, the measured spectrum of CSィイD22ィエD2 used as a standard was enough accurate analyze the Z-scan data.The third order optical nonlinear susceptibility χィイD1(3)ィエD1 in novel low-melting ZnFィイD22ィエD2-SnFィイD22ィエD2-PィイD22ィエD2OィイD25ィエD2 glasses containing Rhodamine 6G and Phthalocyanine as optical activators and tellurite glasses were measured. Satisfactory results have been obtained by these measurements. Real (nonlinear refraction) and imaginary (nonlinear absorption) parts of the third order optical susceptibilities χィイD1(3)ィエD1 were independently measured, which is specific to the Z-scan technique. However, we could not discuss the present results sufficiently because an excitation wavelength of only SHG output from the ps-YAG laser (532 nm) is available at present. We continue investigate the mechanism of the third order optical nonlinearity and to propose novel nonlinear materials which can be utilized for practical application based on the experimental results involving wavelength dispersion of the third order optical nonlinear susceptibility χィイD1(3)ィエD1 by using optical parametric oscillation system. Less