High Harmonic Generation Produced in Molecular Nitrogen using Ultrashort Optical Pulses

Abstract

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

Ultrahızlı Optik Darbeler Kullanılarak Azot Molekülünden Yüksek Mertebeli Harmonik Üretimi

Abstract

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.

Keywords

• Yüksek harmonic üretimi
• XUV
• Ultrahızlı optik
• Nitrogen molekülü

References

1. [1] A. H. Zewail, "Femtochemistry:  Atomic-scale dynamics of the chemical bond," J. Phys. Chem. A, 104, 5660-5694, 2000.
2. [2] X. F. Li, A. L’Huillier, M. Ferray, L. A. Lompré, and G. Mainfray, “Multiple-harmonic generation in rare gases at high laser intensity,” Phys. Rev. A, 39, 5751-5761, 1989.
3. [3] A. McPherson, G. Gibson, H. Jara, U. Johann, T. S. Luk, I. A. McIntyre, K. Boyer, and C. K. Rhodes, “Studies of multiphoton production of vacuum-ultraviolet radiation in the rare gases,” J. Opt. Soc. Am. B, 4, 595-601, 1987.
4. [4] Z. Chang and P. Corkum, “Attosecond photon sources: the first decade and beyond,” JOSA B, 27, B9-B17, 2010.
5. [5] H. C. Kapteyn, M. M. Murnane, and I. P. Christov, “Extreme nonlinear optics: Coherent X rays from lasers,” Phys. Today, 58, 39-44, 2005.
6. [6] K. Ishikawa, “Photoemission and ionization of He+ under simultaneous irradiation of fundamental laser and high-order harmonic pulses,” Phys. Rev. Lett., 91, 043002, 2003.
7. [7] E. J. Takahashi, T. Kanai, K. L. Ishikawa, Y. Nabekawa, and K. Midorikawa, “Dramatic enhancement of high-order harmonic generation,” Phys. Rev. Lett., 99, 053904, 2007.
8. [8] F. Brizuela, C. M. Heyl, P. Rudawski, D. Kroon, L. Rading, J. M. Dahlström, J. Mauritsson, P. Johnsson, C.L. Arnold, and A. L'Huillier, “Efficient high-order harmonic generation boosted by below-threshold harmonics,” Sci. Rep., 3, 1410, 2013.

9. [9] T. Kanai, E. J. Takahashi, Y. Nabekawa, and K. Midorikawa, “Destructive interference during high harmonic generation in mixed gases,” Phys. Rev. Lett., 98, 153904, 2007.
10. [10] S. Eisebitt, J. Luning, W. F. Schlotter, M. Lorgen, O. Hellwig, W. Eberhardt, and J. Stohr, “Lensless imaging of magnetic nanostructures by X-ray spectro-holography,” Nature, 432, 885-888, 2004.
11. [11] J. Itatani, J. Levesque, D. Zeidler, H. Niikura, H. Pepin, J. C. Kieffer, P. B. Corkum, and D. M. Villeneuve, “Tomographic imaging of molecular orbitals,” Nature, 432, 867-871, 2004.
12. [12] M. D. Seaberg, D. E. Adams, E. L. Townsend, D. A. Raymondson, W. F. Schlotter, Y. Liu, C. S. Menoni, L. Rong, C.-C. Chen, J. Miao, H. C. Kapteyn, and M. M. Murnane, “Ultrahigh 22 nm resolution coherent diffractive imaging using a desktop 13 nm high harmonic source,” Opt. Express, 19, 22470-22479, 2011.
13. [13] A. Ravasio, D. Gauthier, F.R.N.C. Maia, M. Billon, J. P. Caumes, D. Garzella, M. Géléoc, O. Gobert, J. F. Hergott, A.M. Pena, H. Perez, B. Carré, E. Bourhis, J. Gierak, A. Madouri, D. Mailly, B. Schiedt, M. Fajardo, J. Gautier, P. Zeitoun, P. H. Bucksbaum, J. Hajdu, and H. Merdji, “Single-shot diffractive ımaging with a table-top femtosecond soft x-ray laser-harmonics source,” Phys. Rev. Lett., 103, 028104, 2009.
14. [14] P.M. Paul, E.S. Toma, P. Breger, G. Mullot, F. Augé, P. Balcou, H. G. Muller, and P. Agostini, “Observation of a train of attosecond pulses from high harmonic generation,” Science, 292, 1689-1692, 2001.
15. [15] M. Lewenstein, “Resolving physical processes on the attosecond time scale,” Science, 297, 1131-1132, 2002.
16. [16] M. Hentschel, R. Kienberger, C. Spielmann, G. A. Reider, N. Milosevic, T. Brabec, P. Corkum, U. Heinzmann, M. Drescher, and F. Krausz, “Attosecond metrology,” Nature, 414, 509-513, 2001.
17. [17] M. Lewenstein, P. Balcou, M. Y. Ivanov, A. L’Huillier, and P. B. Corkum, “Theory of high-harmonic generation by low-frequency laser fields,” Phys. Rev. A, 49, 2117-2132, 1994.
18. [18] P. B. Corkum, “Plasma Perspective on Strong-Field Multiphoton Ionization,” Phys. Rev. Lett., 71, 1994-1997, 1993.
19. [19] N. Ben-Tal, N. Moiseyev, and A. Beswick, “The effect of Hamiltonian symmetry on generation of odd and even harmonics,” J. Phys. B At. Mol. Opt. Phys., 26, 3017-3024, 1993.
20. [20] P. Salières and M. Lewenstein, “Generation of ultrashort coherent XUV pulses by harmonic conversion of intense laser pulses in gases: towards attosecond pulses,” Meas. Sci. Technol., 12, 1818-1827, 2001.
21. [21] P. Salières, A. L'Huillier, and M. Lewenstein, “Coherence control of high-order harmonics,” Phys. Rev. Lett., 74, 3776-3779, 1995.
22. [22] M. Sayrac, “High Harmonic Generation in Ar and N2 Gas Mixture Using Ultrashort High Power Laser System,” J. Inst. Science and Technol., 10, 1659-1665, 2020.
23. [23] T. Kanai, S. Minemoto, and H. Sakai, “Quantum interference during high-order harmonic generation from aligned molecules,” Nature, 435, 470-474, 2005.
24. [24] M. Murakami, “High Harmonic Generation by Short Laser Pulses: Time-Frequency Behaviour and Applications to Attophysics,” PhD thesis, Dept. Phys. Astronomy, Louisiana State University, Louisiana, USA, 2006.
25. [25] J. L. Krause, K. J. Schafer, and K. C. Kulander, “High-Order Harmonic Generation from Atoms and Ions in the High Intensity Regime,” Phys. Rev. Lett., 68, 3535-3538, 1992.
26. [26] I. V. Litvinyuk, K. F. Lee, P. W. Dooley, D. M. Rayner, D. M. Villeneuve, and P. B. Corkum, “Alignment-dependent strong field ıonization of molecules,” Phys. Rev. Lett., 90, 233003, 2003.
27. [27] M. Sayrac, A. A. Kolomenskii, and H. A. Schuessler, “Pressure optimization and phase matching of high harmonics generation in CO2 and C2H2 molecular gases,” J. Electron Spectrosc. Relat. Phenom., 229, 1-6, 2018.
28. [28] K. V. Zhukovsky, “Generation of x-ray radiation in free-electron lasers with two-frequency undulators,” Russ. Phys. J, 60, 1630-1637, 2018.
29. [29] G. Lambert, T. Hara, D. Garzella, T. Tanikawa, M. Labat, B. Carre, H. Kitamura, T. Shintake, M. Bougeard, S. Inoue, Y. Tanaka, P. Salieres, H. Merdji, O. Chubar, O. Gobert, K. Tahara, and M. E. Couprie, “Injection of harmonics generated in gas in a free-electron laser providing intense and coherent extreme-ultraviolet light,” Nature Phys., 4, 296, 2008.
30. [30] O. Culfa, “Laser-driven particle acceleration at near critical density plasmas,” Eur. Phys. J. D, 75, 194, 2021.
31. [31] J.T. Tate and P. T. Smith, “The efficiencies of ıonization and ionization potentials of various gases under electron impact,” Phys. Rev., 39, 270-277, 1932.
32. [32] M. Sayrac, A. A. Kolomenskii, and H. A. Schuessler, “Pressure dependence of high order harmonic generation in nitrogen molecular gas and atmospheric air,” Optik, 179, 994-1000, 2019.
33. [33] B. L. Henke, E. M. Gullikson, and J. C. Davis, “X-Ray interactions: Photoabsorption, scattering, transmission, and reflection at E = 50-30,000 eV, Z = 1-92,” Atom. Data Nucl. Data, 54, 181-342, 1993.