نوع مقاله : مقاله پژوهشی

نویسندگان

1 دانشگاه حضرت معصومه(س)، صندوق پستی: 145-37115، قم- ایران

2 پژوهشکده پلاسما و گداخت هسته‌ای، پژوهشگاه علوم و فنون هسته‌ای، سازمان انرژی اتمی ایران، صندوق پستی: 51113-14399، تهران- ایران

چکیده

پلاسماهای لیزری به­‌عنوان یکی از منابع تولید لیزر پرتو ایکس نرم حایز اهمیت می‌باشد. قابلیت کنترل ضریب بهره پرتو خروجی و کیفیت آن از طریق کنترل پارامترهای لیزر و پلاسما از جمله مزیت‌های این روش است. در این پژوهش، یک پالس دمش به‌همراه یک پیش‌­پالس بر روی هدف ژرمانیم به‌عنوان محیط فعال تقویت‌کننده پلاسمایی می‌تابد و بهره لیزر پرتو ایکس نرم در طول‌موج nm 6/19 محاسبه می‌شود. به‌منظور مطالعه اثر پارامترهای لیزری از قبیل شدت، پهنای پالس و اختلاف زمانی بین دو پالس از کد هیدرودینامیکی MED103 استفاده شده است. نتایج شبیه‌سازی نشان می‌دهد که برای دستیابی به بیشینه بهره لیزر پرتو ایکس نرم یک پهنای پالس بهینه برای پیش‌­پالس و نیز پالس اصلی دمش وجود دارد. به‌علاوه مطابق با نتایج به‌دست آمده با افزایش شدت پیش‌­پالس مقدار بهره لیزر پرتو ایکس نرم ابتدا افزایش و سپس کاهش می‌یابد در حالی‌که با افزایش شدت پالس اصلی دمش، این مقدار به­‌طور پیوسته افزایش می‌یابد. ‌هم‌چنین مناطق بهینه مکانی و زمانی بهره لیزر پرتو ایکس نرم در شرایط مختلف اختلاف زمانی دو پالس آورده شده است.

کلیدواژه‌ها

عنوان مقاله [English]

Optimization of pump laser conditions for production of maximum gain of Ne-like Ge soft x-ray laser

نویسندگان [English]

  • G. Ghani Moghadam 1
  • S. Rezaei 2
  • M. J. Jafari 2
  • A. H. Farahbod 2

1 Hazrat-e Masoumeh University, P.O.BOX: 37115-145, Qom, Iran.

2 Plasma and Nuclear Fusion Research School, Nuclear Science and Technology Research Institute, AEOI, P.O.BOX: 14399-51113, Tehran, Iran.

چکیده [English]

Laser produced plasma can be used as the sources of soft X-ray laser. The ability to control the laser quality and its gain coefficient by controlling laser and plasma’s parameters is one of the advantages of this method. In this study, a pump pulse assistant along with a pre-pulse is irradiated on a geranium target as the plasma active medium, thenthe gain of soft X-ray laser at wavelength 19.6 nm is calculated. In order to analyze the effect of laser parameters such as intensity, pulse length, and time delay between two pulses, MED103 hydrodynamic code has been used. The simulation results show that there is optimal pulse duration for the pre-pulse as well as the main pump pulse to achieve the maximum gain of soft X-ray laser. In addition, according to the results, by increasing the pre-pulse intensity the amount of soft X-ray laser gain initially increases and then decreases, while by enhancing the main pulse intensity, it keeps increasing. Also, the optimal spatiotemporal regions of the soft X-ray laser gain for different time delays of two pulses are given.

کلیدواژه‌ها [English]

  • Laser-plasma interaction
  • Ne-like Ge
  • Soft X-ray laser
  • Plasma active medium
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