Yüksek Güçlü Lazer Sistemi Kullanılarak N2 ve H2 Gaz Karışımında Koherent XUV Radyasyonunun Üretilmesi

Öz

Saf H2, saf N2 ve bunların 1:1 oranında karışımları yüksek harmonik üretiminde çalışılmıştır. 17H'den 35H'ye kadar olan harmonik mertebeler gözlemlendi. Saf H2'den üretilen harmonik spektrum elde edildi, ancak harmonik sinyal, saf N2 ve bunların karışımından üretilen harmonik spektruma kıyasla daha zayıftır. Gaz karışımındaki harmonik verim, saf H2'den gelen harmoniklere kıyasla artar. Harmonik mertebelerin ulaşabileceği maksimum foton enerjisi, iyi bilinen cutoff formülü ile hesaplandı. Deney ve hesaplama sonuçlarıyla elde edilen harmonik mertebeler bir uyum içindedir. N2:H2 karışımında, plato bölgesi harmoniklerine kıyasla daha yüksek harmonikler geliştirilmiştir. Saf N2 veya H2-N2 karışımında 35H mertebelerinde saf H2'ye göre artış gözlendi.

Anahtar Kelimeler

• atomik ve moleküler fiziği
• gaz karışımı
• femtosaniye lazer
• yüksek harmonik üretimi
• aşırı ultraviyole(XUV)

Generation of Coherent XUV Radiation in Gas Mixture of N2 and H2 using High Power Laser System

Öz

High harmonic generation is studied in gas species, namely pure H2, pure N2 and their mixture in 1:1 ratio. Observation of harmonic orders from 17H to 35H orders are well resolved. Harmonic spectrum produced from pure H2 are obtained, but the harmonic signal is weaker compared to that produced from pure N2 and from their mixture. Harmonic yield in gas mixture is enhanced compared to that from pure H2. The maximum photon energy that harmonic orders can reach is calculated with the well know cutoff formula. The experiment and the calculation results are in close agreement. In mixture of N2:H2, the higher harmonics are enhanced compared the plateau region harmonics. The enhancement of 35H orders in pure N2 or H2-N2 mixture is observed compared to pure H2.

Anahtar Kelimeler

• Atomic and molecular physics
• gas mixture
• femtosecond laser
• high harmonic generation
• extreme ultraviolet (XUV)

Teşekkür

I am thankful to A. Kolomenski and H. Schuessler for providing the opportunity to perform the experiments described in this paper at Texas A&M University.

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