Ultrahızlı Optik Darbeler Kullanılarak Azot Molekülünden Yüksek Mertebeli Harmonik Üretimi

Aşırı ultraviyole (XUV) optik darbelerinin üretilmesi, doğrusal olmayan bir yüksek harmonik üretim (HHG) sürecidir. Ultra kısa yoğun lazer darbeleri moleküler nitrojen (N2) üzerine odaklanarak yüksek mertebeli harmonikler elde edilmiştir. Güçlü lazer alan şiddeti bir gaz hücresine odaklanmış ve 54 eV foton enerjisine kadar optik dalgaboyları üretilmiştir. Deneysel olarak en yüksek foton enerjisi 35. harmonik mertebesi olarak gözlemlenmiştir. Harmoniklerin soğurulması (absorpsiyon) harmonik sinyal verimliliğini kısıtlamaktadır. Harmonik verim, gaz hücresi uzunluğu ve ortam basıncı gibi parametre değerlerinden etkilenmektedir. Ortam parametreleri nedeniyle harmonik verim azalmaktadır. Absorpsiyon uzunluğu için simülasyon Mathematica programı kullanılarak yapılmıştır. Harmonik sinyalin değişimi, harmoniklerin absorpsiyonuna atfedildi ve absorpsiyon uzunluğu ile karşılaştırdı.

Anahtar Kelimeler:

Yüksek harmonic üretimi, XUV, Ultrahızlı optik, Nitrogen molekülü

High Harmonic Generation Produced in Molecular Nitrogen using Ultrashort Optical Pulses

Generation of coherent extreme ultraviolet (XUV) pulses is a nonlinear process of high harmonic generation (HHG). HHG produced in molecular nitrogen (N2) medium has been obtained using ultrashort intense laser pulses. The strong laser field was focused onto a gas cell to produce short wavelengths having photon energy up to 54 eV. The highest photon energy is experimentally observed as the 35th order. The absorption of harmonics restricts the harmonic yield efficiency. The harmonic yield is affected by the interaction length and medium pressure. The harmonic yield changes with the medium parameters. The simulation for the absorption length was performed using the Mathematica program. Variation of the harmonic signal has been attributed to the absorption of harmonics, and it is compared with the absorption length.

Keywords:

High harmonic generation, XUV, Ultrafast optics, Molecular nitrogen,

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