Summary form only given. Over the last few years there has been effort in making new materials with large nonlinear refractive index (n/sub 2/) for ultrafast all-optical switching. In particular, chalcogenide glasses have emerged as promising candidates for future optical switching devices due to their large electronic nonlinear refractive indices and ability to produce fibers with them. However, some of the earlier work reported that, at the communication wavelengths (1300 and 1550 nm), the large nonlinearity was coupled with the drawback of photo-darkening initiated by two-photon absorption. Modification in composition of these glasses can lead to significant changes in their linear and nonlinear optical properties. In an attempt to remove photo-darkening we have introduced dopants (Ga/sub 2/S/sub 3/, CsI, Ag/sub 2/S, SnS) that shift the band edge of the samples towards the blue region of the spectrum. The samples still maintain a large nonlinear refractive index but now the most significant multiphoton process, depending on the material composition, is only three, four or even five-photon absorption.
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机译:仅提供摘要表格。在过去的几年中,人们一直在努力制造具有大的非线性折射率(n / sub 2 /)的新材料,以进行超快的全光切换。特别地,硫属化物玻璃由于其大的电子非线性折射率和与之一起生产纤维的能力而已经成为未来的光开关装置的有希望的候选者。但是,一些较早的工作报告说,在通信波长(1300和1550 nm)下,较大的非线性与由双光子吸收引发的光暗化的缺点有关。这些玻璃的成分改变会导致其线性和非线性光学性质发生重大变化。为了消除光暗化,我们引入了掺杂剂(Ga / sub 2 / S / sub 3 /,CsI,Ag / sub 2 / S,SnS),这些掺杂剂将样品的谱带边缘移向光谱的蓝色区域。样品仍然保持较大的非线性折射率,但是现在,最重要的多光子过程(取决于材料成分)仅为三,四甚至五光子吸收。
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