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Date: 26-12-2016
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Date: 21-3-2016
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Date: 10-11-2020
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HIGHER-ORDER NONLINEAR EFFECTS
As we have mentioned earlier, not all materials have a nonlinear a2 coefficient only 10% of all natural crystals do but all materials, including glass, have a third-order coefficient. However, as this coefficient is extremely small compared
Figure 1.1. Generation of high-order harmonics.
to a second-order coefficient, much less efficiency is expected for third-harmonic generation. Calcite, for example, can be used as a third-harmonic generator with efficiencies of less than 10-5. Alternatively, series nonlinear crystals can be used to generate third-harmonic light: the first crystal producing second-harmonic light at 532 nm and the second crystal mixing this light with the original 1064-nm fundamental wavelength, the second crystal often being type I phase-matched. Both methods are outlined in Figure 1.1.
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أمراض منتصف العمر.. "أعراض خطيرة" سببها نقص المغنيسيوم
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لماذا تتناقص أعداد النحل عالميا؟
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ممثل المرجعية العليا: العتبة الحسينية تخطط لإنشاء مراكز متخصصة للكشف المبكر عن (سرطان الثدي) بعموم العراق
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