نوع مقاله : مقاله پژوهشی
نویسندگان
1 پژوهشکده فوتونیک و فن‌آوری‌های کوانتومی، پژوهشگاه علوم و فنون هسته‌ای، سازمان انرژی اتمی، صندوق پستی: 836-14395، تهران – ایران
2 گروه ﻓﯿﺰﯾک، داﻧﺸکده ﻋﻠﻮم پایه، داﻧﺸگاه آزاد اﺳلامی، واﺣﺪ ﺗﻬﺮان ﻣﺮکزی،ﺻﻨﺪوق پﺴتی:69191-14696،ﺗﻬﺮان–اﯾﺮان
3 پژوهشکده چرخه سوخت هسته‌ای، پژوهشگاه علوم و فنون هسته‌ای، سازمان انرژی اتمی ایران، صندوق پستی: 8486-11365، تهران- ایران
چکیده
در این پژوهش، تغییرات زمانی تپ‌های لیزری 2CO TEA که از اتاقکی حاوی گاز 6SF با فشار mbar 150-10 عبور می‌کند، در شاریدگی‌های انرژی و فشارهای گازی مختلف بررسی شده است. نشان داده شده است که برای هر شاریدگی، فشار قطع معینی وجود دارد که در این فشار قطع، میخه تپ لیزری به طور کامل حذف می‌شود، درحالی که دنباله تپ که دربرگیرنده کسر قابل توجهی از انرژی اولیه آن است، برجامی‌ماند. شواهد تجربی برآمده از داده‌های بیناب‌سنجی FTIR، گسست چندفوتونی لیزری مولکول‌های 6SF را پاسخگوی اصلی این رفتارها معرفی می‌نماید.
کلیدواژه‌ها
عنوان مقاله [English]
The role of multi-photon dissociation in TEA CO2 lasers pulse shaping
نویسندگان [English]
- S. Beheshtipour 1 2
- J. Karimisabet 3
- R. Neshati 1
- D. Ahadpour 1
1 Photonic and Quantum Technologies Research School, Nuclear Science and Technology Research Institute, AEOI, P.O.Box: 14395-836, Tehran – Iran|Department of Physics, Central Tehran Branch, Islamic Azad University, P.O.Box: 14696-69191, Tehran - Iran
2 Photonic and Quantum Technologies Research School, Nuclear Science and Technology Research Institute, AEOI, P.O.Box: 14395-836, Tehran – Iran|Department of Physics, Central Tehran Branch, Islamic Azad University, P.O.Box: 14696-69191, Tehran - Iran
3 Nuclear Fuel Cycle Research School, Nuclear Science and Technology Research Institute, AEOI, P.O.Box: 11365-3486, Tehran - Iran
چکیده [English]
In this research, temporal variations in intense TEA CO2 laser pulses passing through SF6 gas-filled cells with a pressure of 10- 150 mbar have been characterized at different energy fluences and gas pressures. It has been shown that for every fluence there is a certain cut-off pressure at which the pulse spike is completely quenched. While the pulse tail escapes, saving appreciable fractions of its initial energy. Experimental evidence along with FTIR spectrometry data have clearly revealed incisive laser-induced multi-photon dissociation of SF6 molecules in these conditions, pronounced as the main responsible for these behaviors.
کلیدواژه‌ها [English]
- CO2 laser pulse shaping
- Multiphoton dissociation
- SF6
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